LIST 



PLATES OF THE CRUSTACEA. 



Fie. 



34 Anthura gracilis. 



35 Idotea tricuspisj 



36 Branchipus stagnalis. 



PLATE 10. 



37 Fluvicola herricki. 



38 (Underside magnified.) 



39 (Upperside ditto.) 



40 Cymothoa triloba. 



— olivacea. 



42 Stenosoma irrorata. 



43 Cerapus tubularis. 



44 Cecrops latreillii. 



45 Argulus alosae. 



46 Caligus americanus(male) 



— — female. 



48 Cypris hispida. 



49 (Valves of the same.) 



PLATE 11. 



50 Polyphemus occidentalis. 



PLATE 12. 



5 1 Homarus americanus. 



52 (Lateral view of the beak. ) 





