74 



THE LIFE OF CRUSTACEA 



of it, and each has at its base a hooked spine which 

 projects inwards and serves for seizing particles of 

 food and passing them into the mouth ; the antennae 

 of the nauplius, in fact, serve as jaws, while it is 

 only later that the mandibles take on this function. 



(see 



Fig. - 29 — Larval Stages of the Prawn — Penceus 



Plate IV.). x 45. (After F. Miiller.) 

 A, Nauplius ; B, young zoea ; C, older zoea ; D, early " schizopod " 



stage 



In the further development of the larva, the body 

 increases in length and becomes divided into somites 

 which increase in number by new somites appear- 

 ing behind those already marked off ; the rudiments 



