METAMORPHOSES OF THE CRUSTACEA. 



281 



In the Opossum-shrimps (Mysis) the young does 

 not leave the pouch of the mother until it is fully 



A. 



Fig. 73. Pen-miissemisulcatvs. A, adult (after deHaan, i^Dat. size) ; 

 B, Zoaaa, and C, less advanced Zoa?a of a species of Pcneevs. X>, 

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



