112 



TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



or Crabs, which have the abdomen permanently tucked 

 up under the carapace, so as not to be visible from above 

 (see fig. XIX.). The 10 conspicuous legs, which give 

 the name " Decapoda," are clearly seen, while smaller 

 ones will be found about the mouth on the under side. 

 The appearance of the edible crab (Cancer pagurus) and of 



Fir;. XVIII., Anornura (natural size). 



the common shore crab (Carcinus mamas) are well known; 

 and the figure shows, at 1 the " Fiddler " or swimming- 

 crab (Portunus puber) with flattened paddle-like hind legs, 

 and at 2 one of the long-legged spider-crabs (Stenor- 

 hynehus phalangium). Some of the spider-crabs are 



