104 SEA-SHORE LIFE 
with nine blunt, smooth-edged teeth along each side of the front 
edge. ‘The claws are sharp but powerful. This is a crawling crab, 
and all the legs end in a sharp spine, there being no paddle-like 
swimming feet. The crab is closely related to the edible crab of 
England and France but, while it is sold in our markets to a limited 
extent, it is not highly esteemed. The shell grows to be three inches 
long and five wide. The eggs are carried about by the female dur- 
ing the summer and hatch as little spined larvee which swim at the 
surface and soon moult and change into little creatures which 
resemble the adults, excepting that the abdomen projects straight 
out in a line with the shell instead of being folded under; and there 
are short spines on the shell which are not seen in the adult. After 
again moulting several times, the larva becomes a little rock crab. 
The adult rock crabs moult in winter, and are then sold in the 
New York market as soft-shelled crabs, although they are not to be 
compared with the more highly esteemed blue crab. 
The Jonah Crab, (Cancer borealis, Fig. 71), is closely related to 
the rock crab, but can be distinguished by its rougher shell, and the 
saw-edged teeth on its front edges. It becomes larger than the rock 
crab, and ranges from the eastern end of Long Island to Nova Sco- 
tia. It lives on rocky shores exposed to the wash of the breakers, 
and does not hide away under stones as does the rock crab. 
The Oyster Crab, (Pinnotheres ostrewm, Fig. 72). The 
female of this*crab lives, when mature, within the gill cavity of 
the oyster, and is highly esteemed as a delicacy, being sold in 
the markets at a high price. In the female the 
| shell is pinkish-white in color and very thin, and 
the legs so weak that the creature could not survive 
away from the protecting oyster. The crab does 

not devour the oyster, but merely lives in associ- 
ation with it. The male crabs, however, swim 
Fie. 72; FEMALE freely over the sea, and they are brown in color with 
OYSTER CRAB. a light colored central stripe, and four whitish 
Long Island Sound. 
ss spots. They are smaller than the females, and 
their shells are hard. The case of the oyster crab is interesting, for, 
while the male has remained active, and has retained a hard shell 
and strong claws and legs, the female has lived a protected life, and 
her shell has degenerated into little more than a soft membrane, while 
