MARINE UNIVALVES 181 
Aleutian Islands. It is of a brownish color and 
has no epidermis. The aperture is large, the sur- 
face rough, and destitute of any spiral sculpturing. 
It is about the same size as the last species. 
Volutopsius attenuatus, Dall, 
the Slender Volutopsius, shown 
in Figure 180, comes from Bering 
Strait and the adjacent Arctic 
waters. The shell is thin, white, 
and delicately striated. The 
length is 58 millimeters. 
Fig. 180 (*) 
Liomesus nux, Dall, 
the Aretic Nut-shell, 
shown in Figure 181, is 
well named, for it much 
resembles a fat nut. It 
comes from the far 
morth. |The shell is Fig. 181, x ¢ @) 
dark colored with a creamy white layer above. 
In life there is a periostracum which resembles 
velvet. It is about the size of a walnut. 
