21 
Part of one side is imperfect. Perlatumbilicate, with depressed but 
not very thick whorls. The area inside the tubercles is narrow and 
divergent. The ventral area is very gently arched. The straight, primary 
ribs end in small conical tubercles. There are about three secondary ribs 
to each primary, two arising by furcation and one by intercalation. The 
secondary ribs are of moderate relief and curve forward a little on the 
venter. The living chamber is not preserved. The suture line is not 
deeply cut; ES is deep; Si is much smaller than ES; S2 is smaller than 
Si and much deeper than broad; LI is as long as EL, but narrower, and 
is not quite symmetrical, having a long median lobule, a short outer 
lobule, and a yet shorter inner lobule; L2 is much shorter than LI; Aux. 
is narrow and inclined. The tubercle is on Si. 
This species closely resembles Stemmatoceras coronation (Quenstedt) 1 
in general proportions, but has more ribs per whorl. The suture line of S. 
coronation is not illustrated, so that comparison with it cannot be made. 
Horizon and Locality. From the base of the Fernie formation on the 
headwaters of Sheep creek, Alberta. 
Type. University of Alberta collections. 
Family, Sphaeroceratidae S. Buckman 
Genus, Saxitoniceras n. gen. 
The inner whorls are sphaeroconic and there is umbilical enlargement 
on the anterior part of the outer whorl. The mouth border has in succes- 
sion behind the lip, a slight elevation, a well-marked furrow, a ridge of 
low relief, and a scarcely defined depression. The primary ribs are rather 
broad and slightlj’’ inclined. The suture line is not deeply cut. L2 is broad. 
This genus differs from Chondroceras Mascke 2 in a two-ridged, at the most, 
not a three-ridged, mouth border, broader primary ribs, not markedly 
inclined forward at the anterior end, and a simpler, less deeply cut suture 
line. It differs from Defonticeras McLearn of the lower Yakoun fauna 
in its simpler suture line, not so lobed or deeply cut, shorter and wider 
LI, and the less abrupt umbilical enlargement. Genotype, Saxitoniceras 
allani, n. sp. 
Saxitoniceras allani n. sp. 
Plate YIII, figures 1, 2 
Diameter 
Height, whorl. . . 
Thickness, whorl 
Width, umbilicus 
Mm. 
Mm. 
43 
36-4 
41-8 
50-6 
55-8 
66-3 
19 
13-7 
The first measurement is taken near the anterior end and the second 
nearly one-half whorl back. The maximum diameter is 45 mm. The 
inner whorls are sphaeroconic and there is umbilical enlargement on the 
anterior part of the outer whorl. Whorls fairly well rounded except for 
a little flattening on the sides, and somewhat contracted at the anterior 
1 Ammon. Schwab. Jura, Pi. 66, fig. 11 (1887). 
1 The writer ia indebted to S. S. Buckman lor the generic characters of Chondroceras. 
