MARINE UNIVALVES 177 
but afterwards withdraws to greater depths. It 
has a light brown covering, under which the shell 
is whitish or purplish, though at the aperture it is 
somewhat pinkish. It is fully five inches in length. 
Three large shells now follow, all of which were 
dredged by the U. 
S. Steamer ‘‘ Alba- 
tross;;. im cold, 
Alaskan waters. 
The first is named 
Strombeélla  fragil- 
2s, Dall, the Fragile 
Strombella, Figure 
Fig. 174, x 3 (*) 
Fig. 173, x 3 (*) 
73. The shell is 
thin and_= inflated. 
Its eolor is pink- 
ish, and there is a 
thin epidermis. 
The outer lip is 
widely — deflected. 
100mm. is about 
the length of this 
large shell. 
Strombella mid- 
