THE CLASSIFICATION OF CRUSTACEA 35 



"Fairy Shrimp" has been given (Fig. 10). It is 

 known in technical zoology as Chirocephalus di- 

 aphanus, and is ' a representative of the subclass 

 BRANCHIOPODA. The members of this group are 

 distinguished from other Crustacea by their flattened, 

 leaf-like feet, each of which is divided into a number 

 of lobes, and has a gill plate on the outer side. In 

 Chirocephalus there is no carapace, and the head is 

 followed by eleven distinct body segments, each 

 bearing a pair of leaf-like, or rather fin-like, feet. 



FIG. 10 THE "FAIRY SHRIMP" (Chirocephalus diaphanus), 

 MALE, x 2. (After Baird.) 



The hinder part of the body has no appendages, 

 and ends in a forked tail. In the female a large 

 pouch hangs from the under-side of the body, just 

 behind the limb-bearing part, and is often found 

 filled with eggs. In the male, a pair of remarkable- 

 looking appendages, each shaped somewhat like a 

 hand with webbed fingers, hang in front of the head. 

 These are connected with the antennae, and are 

 known as the " claspers," from their function in 

 seizing and holding the female. The eyes are set on 

 movable stalks. Those Branchiopoda which, like 



