HOMARUS AMERICANUS MILNE-EDWARDS 123 



FIG. 27. Astacus fluwatilis after Huxley. A, male; B, female; a, anus; 

 gg, opening of green gland (antennal gland, nephridium); Ib, upper lip or 

 labrum; mt, metastoma or under lip; od, opening of oviduct (9 gen. op.); 

 vd, opening of vasdeferens (cf gen. op.); i, stem of eye; 2, antennules; 3, an- 

 tennae; 4, mandibles; 8, second maxillipeds; 9, third maxillipeds; 10, first 

 pereiopod; n, second pereiopod; 14, fifth pereiopod; 15-20, abdominal ap- 

 pendages; X, XI, XIV, sternites of fourth, fifth, and eighth thoracic somites; 

 XVI, sternite of second abdominal somite. 



