METAMORPHOSES OF THE CRUSTACEA. 



281 



In the Opossum-shrimps (Mysis) the young does 

 not leave the pouch of the mother until it is fully 



Fig. 73. PnncFm semuulcatus. A, adult (after de Haan, J nat. sizo"i ; 

 B, Zoaea, and C, less advanced Zoasa of a Bpecies of Pcnmis. D, 

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



