OYSTERS AND SMALL CLAMS 51 
Under the Leptonidae we have quite a number 
of shells, most of them small. 
Fig. 35, x 7 (*) 
Figure 35 gives an en- 
larged view of Hrycina 
compressa, Dall, the Com- 
pressed Erycina, which 
has a thin, white, com- 
pressed — shell, covered 
with a thin, wrinkled per- 
iostracum. It occurs in Bering Sea and south- 
ward as far as Sitka. 
for Venus. 
Krycina is another name 
In Figure 36 we havea singular combination, The 
greater part of the picture 
is a ventral view of the 
Mud Prawn, Gébia puget- 
énsis, Dana, which lives 
in Puget Sound, and is 
very expert in burrowing 
in the soft sand. But at- 
tached to its abdomen is : 
little mollusk, represented 
of natural size, which the 
prawn earries along 
wherever it goes, whether 
willingly or not I do not 
know. This little mollusk 
is named EHrycina rugi- 
fera, Cpr., the Rough Ery- 
eina. It was formerly 
called Lepton rude, Whit- 
eaves. 
We now come to two 
Fig. 36 (*) 
