I 



METAMORPHOSES OF THE CRUSTACEA. 



281 



In the Opossum-shrimps (Mysis) the young does 

 not leave the pouch of the mother until it is full)' 



Fig. 73. Penatns semisulcatus. A, adult (after de Haan, ^ nat. size) ; 

 B, Zosea, and C, less advanced Zoasa of a species of Penceus. D, 

 Nauplius. (B, C, and D, after Fritz Miiller.) 



