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Pennsylvanian Rocks and Fusulinids

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Systematic Descriptions

Genus MILLERELLA Thompson, 1942

MILLERELLA INFLECTA, n. sp.
Plate 1, figures 1-7; plate 5, figures 2, 3; text figure 11

Shell minute, biscuit-shaped, umbilicate; with short axis of coiling, rounded periphery, strongly convex lateral slopes. Mature specimens of 4 1/2 to 6 volutions 0.20-0.25 mm long and 0.36-0.58 mm wide. Form ratio 1:0.51-1:0.48, averaging 1:0.51 for 4 specimens. Average form ratios of first to sixth volution of 3 specimens 1:0.58, 1:0.55, 1:0.56, 1:0.53, 1:0.52, and 1:0.49, respectively. First volution strongly evolute, second to fourth volution almost completely involute, last part of fourth volution to maturity gradually becomes more highly evolute. Last part of sixth volution embraces only about one-third of radius of earlier part of shell (Fig. 11).

Figure 11—Profile outline of Millerella inflecta, n. sp., x 190. [Figure scaled for web presentation.]

Profile outline of Millerella inflecta, n. sp.

Proloculum minute, outside diameter 24-40 microns, averaging 32 microns for 5 specimens. Shell tightly coiled in inner 5 volutions, becomes more expanded immediately over tunnel in sixth volution. Average heights of first to sixth volution immediately over tunnel of 7 specimens 20, 24, 36, 56, 73, and 181 microns, respectively.

Spirotheca thin, composed of tectum and thin upper and lower layers. Becomes only slightly thinner poleward from center of shell.

Septal structure similar to that of spirotheca. Septa slightly arcuate immediately over tunnel, strongly arcuate anteriorly in polar regions. Average septal counts of first to fifth volution of 2 specimens 8, 11, 15, 18, and 23, respectively. Septa unfluted throughout length of shell.

Tunnel about one-third as high as chambers. Tunnel angles measure about 14, 18, and 22 degrees in fourth to sixth volution, respectively. Chomata developed in all parts of shell, except in first volution and outer part of last volution. Chomata about half as high as chambers, tunnel sides essentially vertical, poleward slopes low and extend about half distance from tunnel to polar regions.

Remarks—This form resembles somewhat closely Millerella pinguis Thompson from the Bloyd shale of Arkansas and the Kearny formation of Kansas. However, its shell is smaller for corresponding volutions and is more highly evolute, and its chomata are more massive. M. inflecta can be distinguished from M.? advena Thompson from the Bloyd shale by its larger form ratio for corresponding volutions, more highly umbilicate axial regions, more broadly rounded periphery, and more highly evolute shell.

Measurements of Millerella inflecta, n. sp., Specimens A-G, in millimeters
Volution Height of volution
A B C D E F G
0 .028   .024 .040   .036 .032
1 .028   .020 .014   .020 .016
2 .024 .024 .024 .024   .024 .024
3 .036 .040 .032 .044 .036 .028 .036
4 .061 .053 .065 .048 .048 .040 .077
5 .069   .081 .065 .061 .069 .093
6         .181    
Volution Form ratio of volution Septal count Tunnel angle
(degrees)
A D E F G A D E
1 1:0.58 1:0.59   9 7      
2 1:0.52 1:0.59   12 11      
3 1:0.60 1:0.59 1:0.48 16 14      
4 1:0.52 1:0.54 1:0.52 20 16 14    
5 1:0.55 1:0.50 1:0.51 23 24 18 17 19
6     1:0.49         22

Occurrence—The described syntypes were obtained from Bed 15, Section P-15, Sweetwater Creek, Belden formation. This form is also abundant in the Belden formation, Bed 34 and Bed 40, Section P-13, at Juniper Mountain Canyon, and in Bed 1, Section P-9, Sheep Mountain Canyon.

MILLERELLA CIRCULI, n. sp.
[Name refers to circles (nominative plural).]
Plate 1, figures 15-18

Shell minute, ellipsoidal; with short axis of coiling, rounded periphery, convex lateral slopes, depressed axial regions. Mature specimens of 5 volutions 0.295-0.303 mm long, 0.586-0.626 mm wide. Form ratio 1:0.50-1:0.52. Form ratio gradually decreases with growth of shell. Form ratios of first to fifth volution of holotype 1:0.62, 1:0.70, 1:0.64, 1:0.57, and 1:0.52, respectively. First volution evolute, fourth volution slightly evolute, and fifth volution more highly evolute. Second and third volutions essentially involute. Shell umbilicate throughout growth. Periphery rounded throughout shell, becoming more broadly rounded in outermost volution.

Proloculum minute, outside diameter 40-48 microns, averaging 42 microns in 4 specimens. Shell expands slowly and uniformly. Average heights of first to fifth volution of 4 specimens 22, 33, 56, 83, and 110 microns, respectively.

Spirotheca composed of tectum and thin upper and lower layers. Total thickness of spirotheca about 16 microns in third volution, 20 microns in fourth volution.

Septa thin, extend forward at angle of about 10 degrees in center of shell, arcuate anteriorly in polar regions. Septa unfluted throughout length of shell. Septal counts of first to fifth volution of 2 specimens average 8, 11, 15, 18, and 24, respectively.

Tunnel low and relatively wide. Tunnel angles in third to fifth volution about 17, 22, and 18 degrees, respectively. Chomata developed throughout shell, except in outer few chambers. In third to fifth volution chomata more than half as high as chambers, asymmetrical, with vertical tunnel sides and low poleward slopes. Poleward side extends more than half distance from tunnel to poles.

Remarks—This is one of the largest species of Millerella know from America. In general shape M. circuli resembles M. pinguis Thompson from the Kearny formation of Kansas and the Bloyd shale of Arkansas. However, the polar regions are more deeply umbilicate, its form ratio for corresponding volutions is larger, its chomata are more massive, and its proloculum is larger.

Measurements of Millerella circuli, n. sp., Specimens A-D, in millimeters
Volution Height of volution Form ratio
of volution		 Septal
count		 Tunnel
angle
(degrees)
A B C D A B C D A B
0 .018 .040 .040 .040            
1 .024 .020 .020 .024 1:0.62 1:0.63 7 8    
2 .028 .028 .036 .040 1:0.70 1:0.70 10 11    
3 .057 .053 .057 .057 1:0.64 1:0.69 14 15 17  
4 .085 .081 .081 .085 1:0.57 1:0.61 18 18 22  
5 .101 .121 .113 .105 1:0.52 1:0.50 23 24 18 18

Occurrence—This form is abundant in Bed 52, Section P-10, Split Mountain Canyon, Belden formation, from which the holotype and described and illustrated paratypes were obtained. It is also common in the Belden formation, Bed 15, Section P-15, Sweetwater Creek, and in the lower half of the upper part of Bed 5, Section P-9, Sheep Mountain Canyon. Specimens referred with question to this species occur in Bed 40, Section P-13, Juniper Mountain Canyon, Belden formation.

MILLERELLA cf. M. PRESSA Thompson
Plate 5, figures 1, 4

Millerella pressa THOMPSON, 1944, Kansas Geol. Survey, Bull. 52, pp. 423-425, pl. 2, figs. 16-23.

The specimens from the Belden formation resemble the holotype and para types from the Kearny formation of Kansas somewhat closely in general shape. However, they differ from them especially in that they are narrower for corresponding volutions, have a slightly larger form ratio for corresponding volutions, a smaller proloculum, and more tightly coiled shell. Although they probably represent an undescribed species, a sufficient number of well-oriented sections have not been obtained to feel reasonably sure that internal features are thoroughly understood. The accompanying statistical data were obtained from specimens from the lower 10 feet of Bed 1, Section P-9, Sheep Mountain Canyon, Belden formation.

Measurements of Millerella cf. M. pressa Thompson, Specimens A-C, in millimeters
Volution Height of volution Form ratio
of volution		 Septal
count		 Tunnel
angle
(degrees)
A B C A B C A B
0 .024 .024 .020          
1 .016 .014 .010 1:0.53 1:0.70      
2 .016 .022 .021 1:0.50 1:0.62      
3 .016 .040 .032 1:0.55 1:0.50 14    
4 .040 .050 .040 1:0.48 1:0.49 17    
5 .061 .066 .077 1:0.46 1:0.44 22 20 22
6 .089           22  

Occurrence—In addition to the Sheep Mountain Canyon locality, specimens almost certainly conspecific with the illustrated thin sections are present in Bed 40, Section P-13, Juniper Mountain Canyon, and Bed 15, Section P-15, Sweetwater Creek, Belden formation.

MILLERELLA sp. A
Plate 1, figures 12-14

Shell minute, discoidal; with short axis of coiling, slightly umbilicate polar regions, essentially straight lateral slopes, sharply angular periphery. Inner volutions essentially involute, fifth volution slightly evolute. Specimens of 5 volutions 0.15-0.16 mm long and 0.40-0.44 mm wide. Form ratio 1:0.37-1:0.40. Proloculum minute, outside diameter about 24 microns. Shell tightly coiled. Heights of first to fifth volution about 10, 20, 30, 50, and 77 microns.

Septa slightly arcuate in center of shell, anterior side convex. Septa highly arcuate anteriorly in polar regions. Over tunnel, septa extend anteriorly at angle of about 20 degrees. Septal count of fourth and fifth volutions about 23.

Remarks—The sharply angular periphery, flat lateral slopes, and highly arcuate septa distinguish this form from other American species. It is not possible to draw up a detailed description of this form from the small number of well-preserved thin sections so far obtained. It will be described in more detail after more thorough sectioning and study.

Occurrence—This form is exceedingly abundant in Bed 28 and Bed 37, Section P-15, Belden formation, Sweetwater Creek. The illustrated specimens were obtained from Bed 37.

Genus PSEUDOSTAFFELLA Thompson, 1942

PSEUDOSTAFFELLA cf. P. KEYTEI var. MACCOYENSIS (Thompson)
Plate 1, figures 8-11

Staffella keytei var. maccoyensis THOMPSON, 1935, Jour. Paleontology, vol. 9, pp. 118, 119, pl. 13, figs. 11-15.

Pseudostaffella keytei var. maccoyensis THOMPSON, 1942, Am. Jour. Sci., vol. 240, pp. 408, 410, pl. 1, fig. 24.

Specimens of Pseudostaffella are abundant in much of the Hell's Canyon formation. Beds 26 and 34, Section P-17, Hell's Canyon, contain common specimens that resemble somewhat closely P. keytei var. maccoyensis, originally described from the McCoy formation, near McCoy, Colo. None of my sections is perfectly oriented, but I am illustrating 4 of them and have drawn up the following brief description based on 10 specimens.

Shell minute, subspherical, umbilicate. Orientation of axis changes markedly with development of shell. Axis of first volution normal to that of outer volutions in some specimens. Specimens of 4 to 4 1/2 volutions 0.32-0.34 mm long, 0.36-0.45 mm wide. Form ratio 1:0.7-1:0.9. Form ratios of first to fourth volution about 1:0.8, 1:1.1, 1:1.0, and 1:0.9, respectively.

Proloculum minute, outside diameter 44-65 microns, averaging 56 microns for 4 specimens. Average heights of first to fourth volution of 4 specimens 24, 31, 44, and 65 microns, respectively.

Spirotheca thin, composed of tectum and upper and lower tectoria. Septa of essentially same structure as spirotheca. Septa unfluted throughout length of shell. Septal counts of first to third volution about 6, 8, and 11, respectively.

Tunnel narrow and high. Tunnel angles of third and fourth volutions about 19 and 20 degrees, respectively. Chomata massive, with steep tunnel sides and low poleward slopes.

Remarks—The type specimens of this variety are more tightly coiled for corresponding volutions, and have a larger number of volutions at maturity than any specimens so far discovered at Hell's Canyon.

Occurrence—This form is abundant in parts of the type section of the Hell's Canyon formation and at about the same horizons at Juniper Mountain Canyon. The above description is based entirely on specimens from Hell's Canyon.

Genus FUSULINELLA Möller, 1877

FUSULINELLA IOWENSIS var. LEYI, n. var.
Plate 2, figures 15-25; plate 3, figures 16-21; plate 5, figure 6

Shell small, highly inflated fusiform, straight axis of coiling, steep lateral slopes, sharply pointed poles. Mature specimens of 7 to 8 volutions 2.5-3.4 mm long and 1.5-1.9 mm wide; form ratio 1:1.5-1:1.8, averaging 1:1.6 for 1 specimens. Inner one or two volutions essentially spherical and axis of coiling in some specimens at angles up to 90 degrees to axes of outer volutions. Average form ratios of first to eighth volution of 4 specimens 1:1.0, 1:1.2, 1:1.1, 1:1.5, 1:1.5, 1:1.6, 1:1.6, and 1:1.6, respectively. Thus mature shape of shell attained in fourth to sixth volution.

Proloculum spherical in shape, minute in size in specimens with asymmetrical first volution, small in other specimens. Outside diameter 69-121 microns, averaging 92 microns for 9 specimens. Average heights of first to eighth volution of 6 specimens 33, 44, 59, 79, 108, 138, 169, and 198 microns, respectively. Thus shell expands gradually.

Spirotheca composed of tectum, diaphanotheca, and upper and lower tectoria. Total thicknesses of spirotheca of third to eighth volution of 4 specimens averages about 5, 11, 13, 18, 20, and 24 microns, respectively. Diaphanotheca of essentially uniform thickness in central half of shell but decreases in thickness rapidly in end zones. Tectoria of essentially same thickness throughout length of shell.

Septa composed of tectum and diaphanotheca deflected downward from spirotheca. However, diaphanotheca thins rapidly below top of septa. Average septal counts of first to eighth volution of 2 specimens 12, 15, 19, 22, 26, 27, 32, and 34, respectively. Septal count of innermost asymmetrical volution about 8. Septa straight to broadly wavy in central fourth of shell, fluting forms closed chamberlets in end fourths of shell, septa broadly fluted in remainder of shell.

Tunnel relatively narrow, slightly more than half as high as chambers, path highly irregular. Average tunnel angles of fourth to eighth volution of 4 specimens 15, 16, 16, 18, and 24 degrees, respectively. Chomata massive and broad, about two-thirds as high as chambers. Slope on tunnel side steep, poleward slope low. Chomata reach from tunnel to poles in inner 5 volutions but more nearly symmetrical in outer volutions.

Remarks—This variety may be distinguished from the typical variety, Fusulinella iowensis var. iowensis Thompson, from the lower part of the type Desmoinesian of Iowa by its more elongate shell, more highly fluted septa, more massive chomata in the inner volutions, and more highly inflated and higher chambers in the outer volutions. From F. iowensis var. stouti Thompson from the Mercer limestone of Ohio it can be distinguished by its slightly larger form ratio, more massive chomata, slightly larger size, and more highly fluted septa.

This form is named in honor of Mr. Henry Ley.

Measurements of Fusulinella iowensis var. leyi, n. var., Specimens A-K, in millimeters
Volution Height of volution
A B C D E F G H I J K
0 .081 .097 .097 .069   .081   .121 .113 .085 .089
1 .026 .036 .036 .032   .036 .040 .040 .040 .040 .040
2 .045 .045 .048 .036 .048 .045 .042 .072 .052 .062 .054
3 .054 .072 .073 .045 .054 .054 .077 .081 .085 .081 .090
4 .081 .090 .105 .062 .072 .063 .108 .108 .109 .108 .126
5 .108 .108 .137 .099 .108 .090 .108 .144 .101 .135 .135
6 .117 .144 .173 .126 .144 .126 .180 .198 .161 .180 .189
7 .171 .180 .181 .180 .162 .144       .153  
8 .234     .198 .162 .198          
Volution Form ratio of volution Wall thickness
A B D F H J K A B D E
1 1:1.1 1:1.3 1:1.0 1:1.2 1:1.2 1:1.5 1:1.3        
2 1:1.2 1:1.4 1:1.1 1:1.4 1:1.4 1:1.6 1:1.5        
3 1:1.4 1:1.4 1:1.2 1:1.5 1:1.5 1:1.6 1:1.7 .005      
4 1:1.4 1:1.5 1:1.4 1:1.5 1:1.8 1:1.6 1:1.8 .008   .014 .012
5 1:1.4 1:1.5 1:1.5 1:1.5 1:1.9 1:1.8 1:1.7 .012 .014 .016 .012
6 1:1.4 1:1.6 1:1.6 1:1.6 1:1.9 1:1.6 1:1.7 .016 .020 .020 .016
7 1:1.4 1:1.7 1:1.7 1:1.6   1:1.6   .020 .016 .024 .020
8 1:1.5   1:1.8 1:1.5       .024   .024 .024
Volution Septal count Tunnel angle (degrees)
C D E G I A B D F H J
1 11 8 13 9 11            
2 15   15 13 19            
3 20   18 18 19         18  
4 21   22 24 24 16 12 17   18 18
5 27   24 24 26 17 16 15 14 22 18
6 30   23 30 30 16 15 21 14 23 16
7 34   30     20 16 21 15   19
8 36   30     25   30 17    
Specimens A-F are from Bed 26, Section P-17, Hell's Canyon,
and G-K are from Bed 71, Section P-13, Juniper Mountain Canyon.

Occurrence—This variety is abundant in Bed 26, Section P-17, Hell's Canyon, and Beds 70 and 71, Section P-13, Juniper Mountain Canyon, lower Hell's Canyon formation. At Hell's Canyon it is associated with Pseudostaffella sp. and Millerella sp.

FUSULINELLA UINTAENSIS, n. sp.
Plate 3, figures 6-15

Shell small, inflated fusiform; with straight axis of coiling, bluntly to . sharply pointed poles, convex lateral slopes. Mature specimens of 6 to 7 1/2 volutions 0.9-1.8 mm long, 0.6-0.9 mm wide. Form ratio 1:1.5-1:2.0, averaging 1:1.8 for 4 specimens. Form ratio of holotype 1:2.0. In some mature specimens, including holotype, first volution tightly coiled with form ratio 1:0.6-1:0.8. Form ratios of first to seventh volution of holotype 1:0.6, 1:0.9, 1:1.2, 1:1.5, 1:2.0, 1:2.0, respectively. Thus mature shape of shell reached in about fifth volution.

Proloculum minute in specimens with tightly coiled first volution, small in others. Outside diameter 32-61 microns, averaging 45 microns in 8 specimens. Average heights of first to seventh volution of 6 specimens 20, 30, 38, 59, 74, 98, and 121 microns, respectively. However, corresponding volutions of holotype slightly lower than above figures.

Spirotheca composed of tectum, diaphanotheca, and upper and lower tectoria. Diaphanotheca first recognizable in second and third volutions. Average combined thicknesses of tectum and diaphanotheca in fourth to eighth volution in 4 specimens 8, 10, 12, 15, and 20 microns, respectively. Tectoria of essentially uniform thickness throughout length of shell.

Septa thin, composed of downward deflection of spirotheca. Diaphanotheca thins rapidly below top of septa. Average septal counts of first to seventh volution of 4 specimens 7, 11, 13, 15, 19, 22, and 24, respectively. Septa narrowly fluted in end thirds of shell so as to form closed chamberlets at base of chambers. Lower margins of septa broadly fluted across central part of shell.

Tunnel about two-thirds as high as chambers, relatively narrow. Average tunnel angles of third to seventh volution of 4 specimens 14, 15, 15, 17, and 20 degrees, respectively. Chomata well developed throughout all parts of shell, except outermost chambers. Tunnel sides of chomata vertical to overhanging. Chomata broad in inner volutions, with low slopes on poleward sides; asymmetrical and relatively narrow in outer volution.

Remarks—This species is intermediate in development between Fusulinella and Fusulina and I refer it somewhat arbitrarily to Fusulinella. It can be distinguished from F. haywardi, n. sp., especially in that it is smaller at maturity, has a more inflated shell, smaller tunnel angle, and slightly more highly fluted septa. From F. lounsberyi, n sp., it can be distinguished by its more highly inflated shell, more massive and wider chomata, and more highly fluted septa.

Occurrence—Fusulinella uintaensis is abundant in Bed 34, Section P-17, Hell's Canyon, Hell's Canyon formation. It is associated with common specimens of Pseudostaffella sp. and Eoschubertella sp. and abundant specimens of Millerella sp.

Measurements of Fusulinella uintaensis, n. sp., Specimens A-H, in millimeters
Volution Height of volution Form ratio of volution
C D E F G H E F G H
0 .061 .044 .032 .048 .032 .048        
1 .024   .012 .024   .020 1:0.6 1:0.6   1:0.8
2 .028 .032 .026 .032 .032 .028 1:0.9 1:1.0   1:1.4
3 .044 .032 .032 .040 .044 .036 1:1.2 1:1.2 1:1.4 1:1.7
4 .061 .081 .040 .053 .061 .057 1:1.5 1:1.5 1:1.7 1:1.6
5 .073 .093 .053 .069 .073 .081 1:2.0 1:1.5 1:1.6 1:1.9
6 .093 .121 .085 .081 .093 .113 1:2.0 1:1.5 1:1.6  
7 .129 .127 .093     .133 1:2.0      
8     .109              
Volution Wall thickness
(Tectum + diaphanotheca)		 Septal count Tunnel angle (degrees)
A B C D E G H A B C D E F G H
1               7 7 7          
2               11 10 11 11        
3 .007 .006           13 14 14 13       14
4 .010 .008           15 15 16 15       15
5 .012 .012 .012 .008 .012 .010 .010 20 20 20 17 17 14 12 15
6 .016 .016 .016 .010 .012 .012 .012 25 23 23 19 20 15 14 19
7 .016     .013 .016   .016 27     21 20      
8         .020                    

FUSULINELLA LOUNSBERYI, n. sp.
Plate 2, figures 6-14

Shell minute, inflated fusiform; with straight axis of coiling, pointed poles, slightly concave to convex lateral slopes. Mature specimens of 5 to 6 1/2 volutions about 1.6-2.1 mm long and 0.8-0.9 mm wide, form ratio 1:2.0-1:2.3. First volution essentially spherical. Mature shape of shell first reached in about fourth volution. Average form ratios of first to sixth volution of 5 specimens 1:1.1, 1:1.4, 1:1.8, 1:2.1, 1:2.2, and 1:2.3, respectively.

Proloculum small, outside diameter 48-84 microns, averaging 70 microns for 6 specimens. Shell expands uniformly to fifth volution and more slowly in outer 2 volutions. Average heights of first to seventh volution of 6 specimens 27, 34, 52, 79, 116, 126, and 117 microns, respectively.

Septa thin, numerous. Average septal counts of first to sixth volution of 3 specimens 10, 12, 14, 17, 18, and 19, respectively. Septa straight across central part of shell, broadly wavy in lower margins of extreme polar regions.

Spirotheca thin, composed of tectum, thin diaphanotheca, upper and lower tectoria. Average thicknesses of spirotheca in first to sixth volution of 6 specimens 8, 10, 17, 20, 26, and 30 microns, respectively. However, measurements not consistent for same volution of different specimens or in different parts of chamber in same specimen, due largely to variations of thickness of tectoria across top of chamber. Therefore, above measurements indicate only that spirotheca are thin and increase in thickness with growth of individual.

Tunnel about half as high as chambers, path straight from second volution to maturity. Average tunnel angles of third to sixth volution in 5 specimens 20, 23, 28, and 32 degrees, respectively. Chomata narrow, more than half as high as chambers; tunnel side vertical to overhanging in outer 3 or 4 volutions. Chomata broad, asymmetrical, with low slopes on poleward sides in inner volutions.

Measurements of Fusulinella lounsberyi, n. sp., Specimens A-H, in millimeters
Volution Height of volution Form ratio of volution
A B C D E F B C D E F
0 .084 .084 .048 .064 .057 .081          
1 .028 .032 .024 .024 .024 .028 1:1.7 1:0.8 1:1.0 1:1.0 1:1.9
2 .044 .036 .030 .032 .032 .032 1:2.0 1:1.3 1:1.3 1:1.3 1:1.2
3 .064 .065 .034 .061 .048 .040 1:2.4 1:1.8 1:1.8 1:1.4 1:1.5
4 .081 .101 .060 .085 .065 .081 1:2.5 1:2.3 1:2.1 1:1.9 1:1.7
5 .133 .125 .089 .125 .109 .113   1:2.6 1:2.3 1:2.3 1:1.7
6     .110   .141     1:2.6   1:2.2 1:2.1
7     .117                
Volution Wall thickness Septal count Tunnel angle (degrees)
A B C E F A G H B C D E F
1 .008         8 11 11          
2 .012       .008 12 12 13          
3 .020 .024   .008 .016 12 14 15 20   30 17 13
4 .024 .028 .012 .016 .020 16 18 16 24 20 32 21 13
5 .024 .032 .024 .020 .028 16 18 18 30 21 34 25 29
6     .036 .024       19   34   34 31

Remarks—The unfluted septa and nature of the chomata of this form suggest a relationship to the primitive species of Wedekindellina, W. matura, n. sp., from the lower part of the Youghall formation. A species closely similar to Fusulinella lounsberyi may be ancestral to Wedekindellina.

This form is not closely similar to any previously described American species. Superficially it resembles F. llanoensis (Thomas) from the "Marble Falls" limestone of Texas. However, it is smaller in size, its septa are not as closely fluted, and the development of its tectoria are different. The resemblance of these two forms is believed to be one of general outline and does not necessarily indicate close biological affinities.

This species is named in honor of Mr. D. E. Lounsbery.

Occurrence—This form is exceedingly abundant in Bed 112, Section P-13, Juniper Mountain Canyon, and in Bed 77 of same section (Bed 77 is same as Bed 112, due to repetition by thrust faulting).

FUSULINELLA HAYWARDI, n. sp.
Plate 2, figures 1-5; plate 3, figures 1-5

Shell small, elongate fusiform, straight axis of coiling, straight to slightly convex lateral slopes. Mature specimens of 5 to 6 volutions 2.6-3.1 mm long, 0.9-1.3 mm wide. Form ratio 1:2.8-1:3.2, averaging 1:3.0 for 3 specimens. Shell elongate throughout growth of most specimens. Average form ratios of first to fifth volution of 5 specimens 1:1.8, 1:2.1, 1:2.5, 1:2.8, and 1:2.8, respectively. In most specimens all volutions symmetrical. In some specimens first volution coiled at large angle to outer volutions and has form ratio of about 1:1. However, mature size of shell about same in both types.

Proloculum small, outside diameter 80-97 microns, averaging 85 microns in 7 specimens. Shell expands uniformly with growth. Average heights of first to sixth volution for 8 specimens 37, 55, 84, 124, 161, and 212 microns, respectively.

Spirotheca thin, composed of thin upper and lower tectoria, tectum, and relatively thick diaphanotheca. Diaphanotheca first observed plainly at end of second volution, well developed and thick from near end of fourth volution to maturity. Average thicknesses of spirotheca in first to sixth volution of 7 specimens 8, 14, 18, 22, 24, and 28 microns, respectively.

Septa thin. Diaphanotheca thins rapidly downward from top of septa. Average of septal counts of first to sixth volution of 3 specimens 8, 12, 14, 17, 20, and 22, respectively. Septa straight across central third of shell, broadly but highly fluted in end quarters. Fluting extends to tops of chambers in polar regions.

Tunnel high, elliptical in cross-section. Chomata well developed throughout all except outer few chambers. Tunnel sides of chomata vertical to overhanging, poleward slopes low in inner volutions and steeper in outer volutions. Average tunnel angles of second to sixth volution of 4 specimens 21, 28, 33, 40, and 62 degrees, respectively.

Measurements of Fusulinella haywardi, n. sp., Specimens A-H, in millimeters
Volution Height of volution Form ratio of volution
A B C D E F G H D E F G H
0 .085   .081 .085 .085 .081 .080 .097          
1 .040 .036 .036 .040 .040 .036 .032 .036 1:2.4 1:1.6 1:1.4 1:2.0 1:1.6
2 .065 .053 .057 .061 .048 .053 .048 .053 1:2.5 1:1.9 1:1.8 1:2.0 1:2.1
3 .093 .081 .080 .093 .080 .080 .080 .084 1:3.0 1:2.3 1:2.0 1:2.3 1:2.8
4 .141 .121 .117 .137 .113 .121 .121 .121 1:3.1 1:3.1 1:2.5 1:2.5 1:2.8
5 .166 .161 .161 .170 .174 .150 .161 .145   1:2.9 1:2.8 1:2.5 1:3.2
6     .222                    
Volution Wall thickness
(Tectum + diaphanotheca)		 Septal count Tunnel angle (degrees)
A B C D E F G A B C D E F H
1 .008             9 8 8        
2 .012 .008 .016     .016 .016 12 11 12 23 20 20 19
3 .016 .018 .016   .020 .018   13 14 14 29 24 25 27
4 .020 .016 .024 .020 .032 .020 .024 18 17 16 35 31 33 33
5 .024 .016 .028 .032 .032 .016 .023 20 20 19 40 31 41 47
6     .028                     62

Remarks—This form is larger at maturity, has a larger tunnel angle, smaller form ratio, and more highly fluted septa than Fusulinella lounsberyi n. sp. It is more highly elongate and therefore less highly inflated, has a larger tunnel angle, thicker diaphanotheca, and less well developed tectoria than F. llanoensis (Thomas).

This species is named in honor of Mr. O. T. Hayward who assisted me with the field work on which this report is largely based.

Occurrence—This form is exceedingly abundant in Bed 87, Section P-13, Juniper Mountain Canyon, and in Bed 123 of the same section (Bed 123 is same as Bed 87 due to repetition by overthrusting).

Genus WEDEKINDELLINA Dunbar and Henbest, 1933

WEDEKINDELLINA MATURA, n. sp.
Plate 4, figures 1-12; plate 5, figure 5

Shell small, fusiform; with sharply pointed poles, straight axis of coiling, uniform lateral slopes. Mature specimens of 6 to 7 1/2 volutions 2.2-3.0 mm long and 0.8-1.3 mm wide. Form ratio 1:2.2-1:2.4, averaging about 1:2.3 for 3 typical specimens. Form ratios of first to sixth volution of holotype 1:2.0, 1:2.5, 1:2.7, 1:2.7, 1:2.7, and 1:2.7, respectively. Thus shell of essentially uniform shape for outer 4 volutions. Form ratio of first volution essentially of unit value in many individuals.

Proloculum small, outside diameter 65 to 101 microns, averaging 81 microns for 8 specimens. Shell expands uniformly, average heights of first to eighth volution of 8 specimens 29, 44, 56, 73, 92, 120, 146, and 181 microns, respectively.

Spirotheca composed of tectum, diaphanotheca, and upper and lower tectoria. Diaphanotheca relatively thick. Total thickness of spirotheca in second to sixth volution of 2 specimens averages about 10, 22, 30, 36, and 36 microns, respectively. Tectoria of essentially same thickness throughout length of shell but diaphanotheca thickest in central half of shell.

Septa thin, numerous, unfiuted throughout length of shell. Average septal counts of first to seventh volution of 4 specimens 9, 13, 17, 20, 21, 26, and 30, respectively. Structure of septa essentially same as that of spirotheca, but diaphanotheca thins rapidly below top of septa.

Tunnel slightly more than half as high as chambers, elliptical in cross section, path irregular. Chomata high, asymmetrical; with vertical side adjacent to tunnel and low poleward slope. Axial fillings developed in extreme polar regions and extend toward tunnel with rapidly decreasing thickness. Tunnel angles of third to seventh volution of holotype 22, 22, 21, 25, and 27 degrees, respectively. Average tunnel angles of second to seventh volution for 3 specimens 22, 22, 21, 23, 25, and 26 degrees, respectively.

Remarks—The small size, large form ratio, and light axial fillings suggest that this form is primitive biologically. Although it does not closely resemble any previously described American species, the unfiuted septa, axial fillings, and fusulinellid-type spirothecal structure show clearly that it is referable to Wedekindellina. No other fusulinid was found associated with this form in the Uinta Mountains. However, a primitive species of Fusulina, F. prima, n. sp., occurs only a few feet below it in the Hell's Canyon section.

Measurements of Wedekindellina matura, n. sp., Specimens A-H, in millimeters
Volution Height of volution
A B C D E F G H
0 .101 .085 .093 .089 .085 .085 .065 .089
1 .036 .036 .028 .028 .024 .036 .024 .024
2 .057 .053 .040 .048 .036 .048 .032 .036
3 .073 .061 .061 .057 .044 .053 .048 .048
4 .101 .081 .061 .081 .065 .061 .061 .073
5 .121 .121 .081 .081 .065 .081 .101 .089
6 .141 .141 .133 .129 .081 .121 .121 .089
7 .161   .149 .160 .137   .149 .117
8         .181      
Volution Form ratio
of volution		 Septal count Tunnel angle (degrees)
A G C D E H A B G
1 1:2.0 1:1.2 10 9 8 9      
2 1:2.5 1:2.1 13 13 13 13 24 20  
3 1:2.7 1:2.5 17 16 15 17 20 24 22
4 1:2.7 1:2.4 24 20 16 20 23 19 22
5 1:2.7 1:2.4 24 20 17 23 27 23 21
6 1:2.7 1:2.3 22 23 22 28 28 23 25
7           30   24 27
Specimens A-D are from Bed 44, Section P-9, Sheep Mountain Canyon,
and E-H are from Bed 90, Section P-17, Hell's Canyon.

Occurrence—This species is exceedingly abundant in Bed 90, Section P-17, Hell's Canyon, and in Bed 44, Section P-9, Sheep Mountain Canyon, lower Youghall formation.

WEDEKINDELLINA HENBESTI (Skinner)
Plate 4, figures 13-17

Wedekindia henbesti SKINNER, 1931, Jour. Paleontology, vol. 5, p. 259, pl. 30, figs. 2, 3.

Wedekindellina henbesti THOMPSON, 1934, Univ. Iowa, Studies Nat. History, vol. 16, p. 279.—DUNBAR AND HENBEST, 1942, Illinois Geol. Survey, Bull. 67, pp. 99, 186, pl. 9, figs. 5-8.

Shell small, highly elongate fusiform, slightly irregular axis of coiling, concave to irregular lateral slopes. Mature specimens of 8 1/2 to 9 1/2 volutions 4.3-5.8 mm long and 1.0-1.8 mm wide, form ratio 1:3.8-1:4.1. Average form ratios of first to ninth volution for 3 specimens 1:2.0, 1:2.6, 1:3.5, 1:4.0, 1:4.3, 1:4.3, 1:4.3, 1:4.0, and 1:4.0, respectively. Thus form ratio decreases rapidly to fourth or fifth volution but remains essentially same value from there to maturity.

Proloculum small, spherical to ellipsoidal, outside diameter 65-121 microns, averaging 83 microns for 4 specimens. Shell expands slowly and uniformly. Heights of volutions about same throughout length of shell. Average heights of chambers of first to ninth volution of 3 specimens 24, 25, 33, 42, 61, 88, 94, 125, and 143 microns, respectively.

Spirotheca thin, contains 4 layers-tectum, diaphanotheca, and upper and lower tectoria. Average thicknesses of spirotheca of fifth to ninth volution in specimens 24, 28, 29, 32, and 28 microns, respectively. Diaphanotheca relatively thin but tectoria thick. Although shell of this form is larger than that of Wedekindellina matura, n. sp., diaphanotheca considerably thinner.

Measurements of Wedekindellina henbesti (Skinner), Specimens A-D, in millimeters
Volution Height of volution Form ratio
of volution		 Septal count Tunnel angle (degrees)
A B C D A B C D A B C
0 .081 .121 .065 .101              
1 .028 .024 .020 .024 1:1.2 1:2.9   11      
2 .024 .024 .020 .032 1:1.9 1:4.0 1:1.8 16      
3 .028 .040 .028 .036 1:4.0 1:4.1 1:2.3 18   22  
4 .040 .048 .032 .048 1:3.8 1:5.0 1:3.1 21 13 28 24
5 .060 .069 .053 .060 1:4.2 1:5.1 1:3.6 24 18 30 23
6 .081 .084 .065 .100 1:4.1 1:4.5 1:4.2 29 21 24 25
7 .093 .101 .081 .100 1:4.1 1:4.6 1:4.2 28 25 31 21
8 :121 .149 .109 .121 1:4.1 1:4.0 1:4.0 30 24 43 31
9 .141 .182 .109 .141 1:4.0       30   31
10                 40    

Septa thin and composed of same layers as spirotheca, unfluted throughout length of shell. Septal counts of first to ninth volution of one specimen 11, 16, 18, 21, 21, 24, 29, 28, and 30, respectively. Although septa are not fluted, broad undulations are developed in extreme polar regions of outer volutions.

Tunnel about three-fourths as high as chambers, path irregular, cross section elliptical. Averages of tunnel angles of third to tenth volution for 3 specimens 22, 22, 24, 23, 26, 33, 31, and 40 degrees, respectively. Chomata developed throughout shell except in outermost chambers, highly asymmetrical with steep slopes adjacent to tunnel and low slopes on poleward side. Axial fillings well developed throughout all of shell except in outermost volution.

Remarks—The specimens of this species from the Uinta Mountains are closely similar in size for corresponding volutions, tunnel angles, size of proloculum, development of axial fillings, shape of shell, and other statistical data to the holotype and paratypes from Oklahoma. However, the Oklahoma types contain about one more volution at maturity than the largest specimens here described and illustrated.

Wedekindellina henbesti differs from W. euthysepta (Henbest) especially in that it is larger for corresponding volutions, has lighter axial fillings, more irregular axis of coiling, and more irregular lateral slopes. It is more highly elongate and narrower for corresponding volutions, has thinner axial fillings and wider tunnel angle than W. excentrica (Roth and Skinner). This form resembles W. coloradoensis (Roth and Skinner) closely, but the type specimens of the latter seem to be shorter, have a larger form ratio, and are slightly smaller for corresponding volutions.

Occurrence—Specimens of this form are abundant in Bed 48, Section P-9, Sheep Mountain Canyon, lower Youghall formation, associated with abundant specimens of Fusulina rockymontana (Roth and Skinner).

Genus FUSULINA Fischer-de-Waldheim, 1829

FUSULINA PRIMA, n. sp.
Plate 6, figures 32-38

Shell minute, inflated fusiform; with irregular to curving axis of coiling, convex, concave to irregular lateral slopes, and bluntly pointed poles. Mature specimens of 5 to 6 volutions 2.1-3.2 mm long, 0.9-1.4 mm wide. Form ratio 1:2.2-1:2.6, averaging 1:2.4 for 4 specimens. First volution essentially spherical with large form ratio. Mature shape of shell first attained in third to fourth volution. Average form ratios of first to fifth volution of 4 specimens 1:1.2, 1:1.5, 1:1.9, 1:2.2, and 1:2.3, respectively.

Proloculum minute, outside diameter averages 88 microns in 6 specimens. Shell expands relatively rapidly and uniformly. Average heights of first to sixth volution of 6 specimens 35, 58, 91, 119, 162, and 185 microns, respectively. Chambers of outer volutions become noticeably higher poleward from center of shell.

Spirotheca thin, composed of tectum, thin diaphanotheca, and upper and lower tectoria. Lower part of upper tectorium much less dense than upper part, giving appearance of an upper diaphanotheca. Average combined thickness of tectum and diaphanotheca in fourth volution of 4 specimens 12 microns.

Septa thin, diaphanotheca thins rapidly below top of septa. Septal counts of first to fifth volution of a typical specimen 8, 12, 16, 20, and 26, respectively. Septa highly but broadly fluted in polar regions, broadly fluted in lower margins in central part of shell. Fluting forms closed chamberlets at base of septa from poles to margins of chomata.

Tunnel low, path irregular. Average tunnel angles of third to sixth volution of 4 specimens 22, 24, 28, and 32 degrees, respectively. Chomata third to half as high as chambers, asymmetrical in first 3 to 4 volutions, essentially symmetrical in outer volutions.

Remarks—This is a primitive species of Fusulina. It is not greatly advanced biologically beyond the form from the Hell's Canyon formation described above as Fusulinella uintaensis, n. sp. In fact, the septal fluting of these two forms is developed to about the same degree, Fusulina prima being only slightly more highly fluted. The manner of development of the chomata, the spirothecal structure, and general development of the shell have largely influenced placing these two forms in different genera.

Occurrence—This species is abundant in Bed 87, Section P-17, Hell's Canyon, lower Youghall formation.

Measurements of Fusulina prima, n. sp., Specimens A-F, in millimeters
Volution Height of volution Form ratio of volution
A B C D E F A B C D
0 .085 .101 .073 .105 .085 .077        
1 .032 .028 .032 .040 .040 .040 1:1.2 1:1.2 1:1.4 1:1.2
2 .053 .048 .061 .061 .061 .065 1:1.6 1:1.3 1:1.7 1:1.5
3 .101 .061 .093 .077 .101 .113 1:2.1 1:1.7 1:2.3 1:1.6
4 .121 .101 .125 .089 .141 .141 1:2.4 1:2.2 1:2.4 1:1.8
5 .182 .141 .162 .141 .185   1:2.2 1:2.6 1:2.4 1:2.1
6   .173 .202 .181            
Volution Wall thickness
(Tectum + diaphanotheca)		 Septal count Tunnel angle (degrees)
B C E F E F A B C D
1         8 9        
2         12 12        
3 .008       16 13 22   28 17
4 .012 .012 .012 .012 20 18 24 23 26 21
5 .012 .016     26     32 28 26
6               38 26 33

FUSULINA PRISTINA, n. sp.
Plate 5, figures 7-18

Shell small, inflated fusiform; with straight axis of coiling, convex to straight lateral slopes, sharply pointed poles. Mature specimens of 6 to 7 volutions 2.3-3.2 mm long 1.4-1.9 mm wide. Form ratio 1:1.7-1:1.9. First volution subspherical, mature shape of shell first reached in third to fourth volution. Average form ratios of first to seventh volution of 3 specimens 1:1.3, 1:1.6, 1:1.6, 1:1.7, 1:1.8, 1:1.8, and 1:1.9, respectively.

Proloculum small, outside diameter 77-105 microns, averaging 86 microns in 5 specimens. Shell expands slowly. Average heights of first to seventh volution of 6 specimens 40, 54, 94, 128, 170, 201, and 216 microns, respectively. Heights of chambers essentially same throughout length of shell.

Spirotheca thin, composed of tectum, diaphanotheca, and thick upper and lower tectoria. Average thickness of combined tectum and diaphanotheca in fourth to seventh volution of 5 specimens 17, 20, 22, and 24 microns, respectively.

Septa thin, numerous. Septal counts of first to seventh volution of a typical specimen 11, 14, 15, 20, 23, 27, and 30, respectively. Septa fluted throughout length of shell, fluting forms closed chamberlets in lower part of chambers from poles to edge of tunnel. Septa more strongly fluted in polar regions.

Chomata developed throughout shell, except in outer few chambers, essentially symmetrical in outer volutions, highly asymmetrical in inner 4 to 5 volutions. Average tunnel angles in second to seventh volution of 4 specimens 19, 18, 19, 19, 22, and 20 degrees, respectively.

Measurements of Fusulina pristina, n. sp., Specimens A-F, in millimeters
Volution Height of volution Form ratio of volution
A B C D E F A B D
0 .081 .077   .085 .105 .081      
1 .036 .044 .045 .040 .040 .032 1:1.1 1:1.3 1:1.5
2 .048 .061 .063 .053 .048 .048 1:1.6 1:1.6 1:1.5
3 .097 .101 .090 .121 .073 .081 1:1.6 1:1.6 1:1.6
4 .109 .129 .144 .161 .105 .121 1:1.7 1:1.7 1:1.7
5 149 .158 .162 .242 .129 .173 1:1.7 1:1.9 1:1.9
6 .190 .178 .180 .282 .173 .202 1:2.0 1:1.7 1:1.7
7 .230       .202   1:1.9    
Volution Wall thickness
(Tectum + diaphanotheca)		 Septal count Tunnel angle (degrees)
A B C D E E F A B C D
1           11 9        
2           14 13   19    
3           15 16 26 15 16 15
4 .018 .020   .016 .014 20 16 20 17 20 17
5 .020 .020 .020 .020 .020 23 18 22 14 22 19
6 .028 .020 .024 .020 .020 27 26 24 13 22 28
7         .024 30   20      

Remarks—In size and general shape, this form resembles Fusulina pumila Thompson from the lower Cherokee of Iowa. However, its septa are not as narrowly and highly fluted and its chomata have different shapes and degree of development. This species also resembles in general shape Fusulinella uintaensis, n. sp., but it is larger at maturity, has more highly fluted septa, and more nearly symmetrical and narrower chomata.

Occurrence—This form is abundant is Bed 146, Section P-13, Juniper Mountain Canyon, lower Youghall formation.

FUSULINA ROCKYMONTANA Roth and Skinner
Plate 5, figures 19-25

Fusulina rockymontana ROTH AND SKINNER, 1930, Jour. Paleontology, vol. 4, pp. 344, 345, pl. 31, figs. 4-6.—THOMPSON, 1936, Jour. Paleontology, vol. 10, p. 109, pl. 16, figs. 10, 11.—DUNBAR AND SKINNER, 1937, Univ. Texas, Bull. 3701, p. 746, pl. 43, figs. 3, 8.

Specimens here referred to Fusulina rockymontana are abundant in the lower part of the Youghall formation along the southeast and northeast margins of the Uinta Mountains. They have been compared directly with topotype specimens from the McCoy formation at McCoy, Colo., and are considered conspecific. Detailed specific descriptions are not deemed necessary but statistical data for the Uinta Mountain specimens are given.

The septal fluting, development of the chomata, and general shape of the shell of Fusulina rockymontana are closely similar to those of F. euryteines Thompson from the Cherokee of Iowa. The detailed internal features of these forms differ in several respects. The inner volutions of F. rockymontana are slightly more loosely coiled and its chomata deposits do not spread laterally as heavy or wide as in F. euryteines. Also, the form ratios of corresponding volutions of F. rockymontana are smaller and the proloculum is larger.

Measurements of Fusulina rockymontana Roth and Skinner, Specimens A-E, in millimeters
Volution Height of volution Form ratio of volution
A B C D E A B C
0 .162 .162 .141 .180 .141      
1 .054 .057 .041 .057 .044 1:1.7 1:1.6 1:1.4
2 .063 .077 .057 .085 .061 1:2.1 1:1.8 1:2.0
3 .108 .097 .077 .105 .081 1:2.3 1:2.1 1:2.3
4 .126 .129 .097 .137 .125 1:2.6 1:2.2 1:2.6
5 .170 .141 .150 .181 .150 1:3.1 1:2.3 1:2.6
6 .180 .181 .178 .190 .202   1:2.3 1:2.8
7   .182 .194 .242 .185  
Volution Wall thickness Septal count Tunnel angle (degrees)
A B D E D E A B C
1         14 12      
2         21 20      
3         26 23 17 17 20
4 .014   .012 .012 29 26 22 22 22
5 .020   .014 .016 36 28 37 24 32
6   .028 .029 .020 32 32 40 30 40
7       .028 32 35 52 33 54

Occurrence—Specimens of this form are abundant in Bed 48, Section P-9, Sheep Mountain Canyon, from which the illustrated specimens were obtained. At this locality it is associated with abundant specimens of Wedekindellina henbesti (Skinner). This species was originally described from the McCoy formation at McCoy, Colo. Probably conspecific specimens are common in the Hartville area of eastern Wyoming.

FUSULINA CURTA, n. sp.
Plate 6, figures 10-16

Shell short, highly inflated fusiform; with straight axis of coiling, convex lateral slopes, bluntly pointed poles. Mature specimens of 7 1/2 to 9 volutions 3.1-3.8 mm long, 2.0-3.9 mm wide. Form ratio 1:1.4-1:1.5. In many specimens shell retains essentially same shape throughout growth. In some, form ratio of first volution slightly smaller than that of mature shell. Average form ratios of all volutions in 4 specimens 1:1.5. A few specimens have form ratio of first volution 1:1.7 and that of mature specimen 1:1.4.

Measurements of Fusulina curta, n. sp., Specimens A-G, in millimeters
Volution Height of volution Form ratio of volution
A B C D E F G A B C D
0 .162 .108 .108 .234 .141 .145 .141        
1 .054 .054 .052 .072 .052 .052 .065 1:1.4 1:1.7 1:1.6 1:1.2
2 .061 .072 .073 .090 .077 .081 .085 1:1.5 1:1.6 1:1.8 1:1.3
3 .095 .090 .105 .099 .093 .121 .101 1:1.5 1:1.5 1:1.7 1:1.4
4 .144 .126 .141 .144 .145 .153 .121 1:1.5 1:1.6 1:1.7 1:1.4
5 .144 .144 .161 .162 .162 .173 .161 1:1.4 1:1.6 1:1.6 1:1.4
6 .180 .162 .181 .216 .186 .206 .165 1:1.4 1:1.5 1:1.6 1:1.4
7 .216 .180 .193 .270 .242 .226 .189 1:1.4 1:1.6 1:1.6  
8 .216 .234     .222 .242     1:1.4    
9   .216                  
Volution Wall thickness
(Tectum + diaphanotheca)		 Septal count Tunnel angle (degrees)
B E F E F G A B C D
1       11 13 13        
2       18 18 21        
3       25 24 26 10 12 15 10
4     .010 30 27 31 11 13 17 11
5   .009 .012 33 34 36 10 11 11 13
6 .012 .012 .016 32 34 31 12 13 16 14
7 .016 .020 .020   41 44 16 13 15 17
8 .020 .020   44 52     15    
9               28    

Proloculum minute, outside diameter 108-162 microns in 6 specimens, averaging 134 microns. In one specimen, outside diameter 234 microns. Shell expands slowly and uniformly. Average heights of first to ninth volution of 7 specimens 67, 90, 101, 140, 158, 185, 216, 228, and 216 microns, respectively.

Spirotheca thin. Diaphanotheca thin but well developed from near end of first volution to maturity. Average combined thicknesses of tectum and diaphanotheca in fourth to eighth volution of 3 specimens about 10, 11, 13, 19, and 20 microns, respectively.

Septa thin. Diaphanotheca extends almost to base of septa in center of shell. Septa fluted throughout shell, in outer volutions fluting forms closed chamberlets for more than half height of chambers immediately over tunnel. Average septal counts of first to eighth volution of 3 specimens 12, 19, 25, 34, 32, 42, and 48, respectively.

Tunnel narrow, path slightly irregular. Average tunnel angles in third to ninth volution of 4 specimens 12, 13, 11, 14, 15, and 28 degrees, respectively. Chomata half to four-fifths as high as chambers, both sides essentially vertical in center of chambers. Deposits extend laterally from chomata to form thick deposits on septa and floors of chambers.

Remarks—In general shape, this form resembles Fusulina girtyi (Dunbar and Condra) more closely than any other American species. However, it is smaller at maturity, has less intensely fluted septa, lighter chomata deposits, and smaller septal counts for corresponding volutions.

Occurrence—This species is abundant in Bed 191, Section P-13, Juniper Mountain Canyon, Youghall formation.

FUSULINA spp.

Form A
Plate 6, figures 1-9

Form B
Plate 6, figures 17, 18, 22, 23

Form C
Plate 6, figures 19-21

Form D
Plate 6, figures 24-31

An abundant fauna of the genus Fusulina occurs throughout the Youghall formation in the Uinta Mountains, in addition to the forms described above. Additional sections must be prepared of some of them, however, before their nature can be understood with some degree of assurance and before their relationship to other species can be determined. However, it will suffice at this time to illustrate typical specimens of some of the more abundant forms and to give statistical data obtained from some of them.

Occurrence—Specimens of Form A are abundant in Bed 206, Section P-13, Juniper Mountain Canyon; Forms Band C are abundant in Bed 61, Section P-9, Sheep Mountain Canyon; and Form D is abundant in Bed 101, Section P-17, Hell's Canyon. All are from the upper part of the Youghall formation.

Measurements of Fusulina sp., Form A, Specimens A-F, in millimeters
Volution Height of volution Form ratio of volution
A B C D E F A B C D
0 .121 .113 .101 .101 .085 .089        
1 .048 .040 .036 .032 .032 .032 1:1.8 1:1.3 1:1.6 1:1.5
2 .073 .048 .057 .057 .053 .040 1:1.8 1:1.7 1:2.0 1:2.1
3 .101 .089 .085 .081 .081 .081 1:2.2 1:1.7 1:2.4 1:2.3
4 .165 .105 .117 .121 .113 .093 1:2.3 1:2.4 1:2.6 1:2.8
5 .202 .174 .157 .161 .161 .125 1:2.8 1:2.7 1:2.9 1:3.0
6   .194 .210   .202 .194   1:2.7 1:3.0  
7           .202        
Volution Wall thickness Septal count Tunnel angle (degrees)
B E F E F A B C D
1       8 9        
2       13 15 24      
3       15 15 23 18 20 25
4       17 20 27 20 23 33
5 .016 .016 .016 21 22 30 25 27 36
6       27 26   32 30  
7     .020   28        

Measurements of Fusulina sp., Form C, Specimen B, in millimeters
Volution Height of
volution		 Form ratio
of volution		 Wall thickness Tunnel angle
(degrees)
B B B B
0 .081      
1 .040 1:1.2    
2 .049 1:1.3    
3 .085 1:1.9   16
4 .093 1:2.1 .012 24
5 .141 1:2.5 .012 24
6 .1,7 1:2.3 .016 23
7 .242     25

Measurements of Fusulina sp., Form D, Specimens A-F, in millimeters
Volution Height of volution Form ratio of volution
A B C D E F A B C D
0 .109 .141 .109 .093 .109 .149        
1 .040 .036 .032 .036 .052 .044 1:1.2 1:1.3 1:1.4 1:1.4
2 .065 .061 .061 .053 .069 .056 1:2.0 1:1.7 1:1.8 1:2.0
3 .093 .085 .065 .069 .085 .101 1:2.2 1:2.3 1:2.4 1:2.2
4 .129 .101 .093 .105 .125 .133 1:2.5 1:2.4 2:2.6 1:2.6
5 .162 .153 .101 .161 .162 .169 1:2.4 1:2.4 1:3.1 1:2.3
6   .202 .141   .180       1:2.5  
Volution Wall thickness
(Tectum + diaphanotheca)		 Septal count Tunnel angle (degrees)
A B D E E F A B C D
1         10 11        
2         17 19 25      
3     .008   19 20 30 22 23 22
4 .016   .012 .012 21 22 27 36 30 30
5 .016 .020     27 26 28 36 35 37
6         28     40 38  

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Kansas Geological Survey, Geology
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