34 



COLLEGE ZOOLOGY 



prawnlike crustacean called My sis (Fig. 217), and is said to be 

 in the Mysis stage. 



The shrimp, Penceus, passes through a number of interesting 

 stages before the adult condition is attained. It hatches as a 



FIG. 227. Two later stages in the development of Penceus. A, Zocea 

 stage. B, Mysis stage. (From Korschelt and Heider, after Claus.) 



larva, termed a Nauplius (Fig. 226, A), possessing a frontal eye 

 and three pairs of appendages (A f , A", Mdf.); this Nauplius 

 molts and grows into a Protozocea stage (Fig. 226, B), which bears 

 three more pairs of appendages and the rudiments of segments 

 III-VIII. The Protozocea stage grows into the Zocea stage 



