1915] PALAEOZOIC FOSSILS FROM Hupson Bay. ra 
Mould of the exterior of a small trochiform shell. Basal diameter 
16mm. Height 11 mm. Sides flat. Sutures scarcely visible. Whorls 
marked by three rounded ridges separated by sharp depressions. Silu- 
rian, Limestone rapids, Severn river. 
No. 378 S. Royal Ontario Museum of Palaeontology. 
Fragment of the cast of a body whorl of a small shell of about 13 mm. 
in diameter. The whorl is rounded above and with a sharp peripheral 
keel at the lower margin. While much smaller than Euomphalopterus 
valeria, the fragment has almost exactly the outline of this species as 
figured by Whiteaves. (Geol. Sur. Can., Palaeoz. Foss., Vol. III, pl. 
fig. Ia. Silurian, Limestone rapids, Severn river. 
No. 379 S. Royal Ont. Museum of Palaeontology. 
Imperfect cast of a small shell with rounded whorls and deep sutures 
suggesting the genus Holopea. Silurian, Limestone rapids, Severn river. 
No. 380 S. Royal Ontario Museum of Palaeontology. 
One distorted internal cast suggesting Strophostylus filicinctus, . 
Whiteaves. See page 67. Silurian, Limestone rapids, Fawn river. 
No. 381 S. Royal Ontario Museum of Palaeontology. 
Fragments of moulds of the apical side of a large shell which may 
possibly be the form herein described as Pycnomphalus colemani but 
which could not be referred to any other species of this report. Silurian, 
Limestone rapids, Severn river. 
No. 382 S. Royal Ontario Museum of Palaeontology. 
Fragment of a cast of a small Euvomphalus about 15 mm. in maximum 
diameter. The spire is slightly ascending. The body whorl is obtusely 
sub-angular above and rounded below. Apparently differs from any 
other species in the collection. Silurian, Severn river. 
No. 411 S. Royal Ontario Museum of Palaeontology. 
MULTISPIRAL OPERCULA OF GASTROPODS. 
The collection contains three multispiral opercula derived from 
two different species. One type shows a diameter of 16 mm. with 
about six coils; the other is somewhat larger, 26 mm. in diameter with 
an indeterminate number of coils. 
Locality—Limestone rapids, Severn river, District of Patricia, Ontario. 
Horizon—Silurian. 
No. 416 S. Royal Ontario Museum of Palaeontology. 
