97 
Sonninites skawahi n. sp. 
0 Skawah } an Indian legendary name) 
Plate XXI Y, figures 1, 2 
Diameter 
Height of whorl 
Thickness of whorl 
Width, umbilicus 
*very approximate 
55 mm. 
40% 
31-3 
38-2 
The specimen is entirely septate and the outer whorl or whorls are 
not preserved. The preservation is almost entirely in the form of core, 
i.e. mould of the interior. Allowance is made in the measurements for 
a keel 2 mm. high. 
Slightly compressed serpenticone, latumbilicate, the whorls moder- 
ately embracing, somewhat compressed ovate, and flattened on the sides. 
The venter broad and gently rounded. The keel, which is not preserved, 
leaves on the core a ridge and two narrow sulci. The size of the keel is 
unknown. On the sides, the strong ribs are almost straight and ventrally 
they curve forward; but the total amount of forward curvature cannot 
be determined, owing to the absence of test; it must be considerable, 
however, each rib overlapping the next. The ribs are jugate on the inner 
margin. 
The suture line is complex. The external saddle is deep, moderately 
broad, and divided by a small lobule. The lateral saddles are deep and 
extremely narrow. The first lateral lobe is cruciform, rather broad- 
stemmed, and longer than the external lobe. The second lateral lobe is 
long and very narrow. The auxiliary lobe is short and slanting. There 
is no retraction of the inner end of the suture-line, however. 
Owing to absence of the outer whorl, a complete comparison of this 
species with Sonninites silveria n. sp. cannot be made, but they certainly 
differ in details of the suture-line, for S. skawahi has much narrower and 
more deeply cut lateral saddles and a longer and more slender median 
lobule in the first lateral lobe. S. skawahi is very close in form, proportions, 
and suture-line to Sonninites alsaticus (Haug), 1 but has higher whorls, 
somewhat weaker ribs, and much less ventral sulcation. Compared with 
A. tessonianus falcatus Quenstedt 2 the Canadian species has higher and 
thinner whorls, less umbilication (i.e., a smaller umbilicus), and probably 
a smaller keel. The Canadian species is an advance in development over 
both of these European species. 
Horizon and Locality. From talus of the middle sedimentary division 
of the Hazelton group, exposed in a cliff about 1 mile southeast of Silver 
lake, Hudson Bay mountain, B.C. 
Type: Victoria Memorial Museum; holotype, Cat. No. 7709. 
i See Buckman, S. S.: Type Ammonites, vol. VI, Pis. 528, 528A (1925). 
a Ammon. Schwab. Jura; PL 63, fig. 10. 
