262 



CRUSTACEA. 



Fio. 120. Three later larval stages of Lucifer (after BROOKS). A, younger Mysis- or Schizopod- 

 like stage. B, older Mysis- or Schizopod-like stage less highly magnified. C, Mastigopus 

 stage, a', first antenna ; a", second antenna; ab l -ab 6 , the six pleopoda; c, cephalo-thoracic 

 shield ; dr, antennal gland ; en, flagellum, and ex, scale of the second antenna ; md, 

 mandible ; mf 1 , first maxillipede ; mf", second maxillipede ; mx 1 , first maxilla ; mx", second 

 maxilla ; o, compound eye ; oc, Nauplius eye ; ol, upper lip ; r, rostrum ; 1-6, six abdominal 

 segments. 



