70 TRANSACTIONS OF THE ROYAL CANADIAN INSTITUTE. [VOL. XI 
GASTROPODA, indet. 
In addition to the more or less distinct and determinable Gastro- 
poda already listed, the collection contains a number of fragments 
which evidently belong to still other species, but which are quite in- 
capable of determination. Brief notes on these specimens follow: 
Fragment of mould of the exterior. Indicates a shell of about 60 mm. 
in diameter and about 35 mm. high. Four whorls shown; probably six 
or seven in all. Whorls rounded above and slightly concave on the 
lower lateral aspect. A wide alar expansion extending at least 10 mm. 
from the periphery of the body whorl and marked by fine curved lines 
of growth. This expansion is not observed on the upper whorls, but its 
probable existence cannot be denied. There is some evidence of a 
raised band on the superior lateral aspect of the whorls. Apical angle 
about 70°. 
Probably a Euomphalopterus of the type of E. velaris, Billings sp. 
or E. valeria, Billings sp. Silurian, Limestone rapids, Severn river. 
No. 372 S. Royal Ontario Museum of Palaeontology. 
Fragment of the cast of a body whorl indicating a shell 48 mm. in 
diameter. The outline is very sloping above and obtusely rounded at 
the inferior edge. The height measured in the direction of the sloping 
side is 11 mm., while the direction at right angles, z.e., the thickness of 
the whorl, is only 7 mm. None of the described species possess a body 
whorl of this character. Silurian, Limestone rapids, Severn river. 
No. 373 S. Royal Ontario Museum of Palaeontology. 
Fragment of a body whorl indicating a turreted type of shell. The 
whorl is 17 mm. high; it is distinctly concave on the superior lateral 
aspect for a width of 7 mm. from the suture to a sharply marked revolv- 
ing ridge. Below the ridge the outline is again broadly concave to near 
the inferior lateral margin, beyond which it is convex. This shell is 
distinctly different from any other described in this contribution; it 
suggests the genus Lophospira. Silurian, Assina rapids, Severn river. 
No. 374 S. Royal Ontario Museum of Palaeontology. 
Two fragments of casts probably referable to Coelidium or to Hor- 
motoma. One is slightly angulated a little above the mid-height, and 
the other shows a rounded whorl a little expanded in the lower half. 
The first of these specimens may belong to Coelidium macrospira and 
I should ascribe the second to Hormotoma whiteavesi except for the fact 
that the apical angle is larger than in the other specimens which I have 
placed in that species. Silurian, Limestone rapids, Severn river. 
No. 376 and 377 S. Royal Ontario Museum of Palaeontology. 
