I 
12 
Goniobasis williamsi sp. nov. 
Plate III, figure 8 
This species resembles G. tenuicarinata of the Willow Creek and 
Paskapoo formations in its ornamentation, but differs in its greater com- 
parative breadth, more widely divergent apical angle, and in the fact that 
the upper carina is always larger in comparison with the second carina, 
and always coincides with the widest part of the whorl. It also occurs at 
a considerably lower horizon. G. williamsi also closely resembles G. sub- 
tortuosa, differing only in the additional ornamentation. In cases of poor 
preservation it is difficult to ascribe a specimen to its proper place. The 
species is named after Dr. M. Y. Williams who collected the type speci- 
mens. It occurs only in the Foremost member of the Belly River for- 
mation. 
Dimensions of Type. Length, 17 mm.; breadth, 10 mm.; apical angle, 
45 degrees. 
Goniobasis judithensis minimus var. nov. 
Plate III, figure 12 
This variety differs from the type species only in its smaller size. 
Whereas Stanton^ states that G. judithensis is lai^er than G. tenuicarinata 
and averages 22 mm. in length by 13 mm. in breadth, our forms do not 
average more than 10 mm. in length by 7 mm. in breadth, and the largest 
specimen is only 16 mm. long. It is abundant at two localities in the Pale 
beds and other specimens were collected from beds of doubtful ages in 
Oyster creek one-half mile from Oldman river. 
Dimensions of Type. Length, 9 mm.; breadth (flattened), 8 mm.; 
apical angle, 60 degrees. 
Goniobasis whittakeri sp. nov. 
Plate III, figure 11 
Shell variable in size, moderate to small; whorls seven, moderately 
convex, those near the apex slender and uniformly rounded, the lower 
whorls angulated at the middle, the body whorl almost flat above the 
angle and convex below, whorls immediately above the body whorl flat 
both above and below the angle; surface marked by numerous (about 
forty in each whorl), evenly spaced, fine, revolving strife, an equal number 
above and below the angle; strise slightly waving where crossed by faint 
irregular lines of growth, presenting a silky appearance to the surface of 
the shell; aperture ovate. 
Comparatively abundant in the St. Mary River formation and a few 
specimens have also been found in the Edmonton formation. The forms 
from the St. Mary River formation described by Whiteaves^ as a new 
variety of G. tenuicarinata are undoubtedly poorly preserved examples of 
this species, and the specimens referred by him (op. cit., p. 21, PI. 3, figs. 
4, 4a) to G. nebrascensis also belong to it. 
iStanton, T. W.: U.S. Geol. Surv., Bull. 257, p. 117, PL 13, fig. 4 (1906). 
‘Gcol. Surv., Canada, Cont. Can. Pal., vol. 1, p. 22, PL 3, figs. 6, 6a. 
