ASELLUS AQUATICUS. 



ISOPODA. 



NORM AH A. 



343 



ASELLID^. 



ASELLUS AQUATICUS. 



Specific character. Upper an tennis reacbing to the extremity of the 

 peduncle of the lower; flageUum of the lower twice the length of the 

 peduncle. Pereion of a greyish colour, mottled with paler markings ; pedun- 

 cle of the caudal appendages nearly half the length of the slender terminal 

 subequal filaments. 



Length of the male, nearly half an inch ; female, much smaller. 



Oiiiscus aquaticiis. Linn. Syst. Nat. ii. p. 1061. Roejier, Gen. Ins. 



pL 30, fig. 12. 

 Cymotkoa aquatica. Fabricius, Ent. Syst. ii. p. 505 ; Ejusd. Suppl. 



p. 303 {Idotea aq.). 

 VAselle. Geoffroy, Ins. Paris, ii. p. 672, t. 22, f. 2. 



Asellus aquatlcus. Olivier, Enc. Meth. iv. p. 252. Leach, Trans. 



Linn. Soc. xi. p. 373. Guerin MbnevHjLE, 



Icon. R. An. Crust, t. 31, f. 3. Samouelle, 



Ent. Compend. p. 110. White, B. M. Cat. 



Brit. Crust, p. 69; Pop. Hist. Brit. Crust. 



p. 230, pi. 12, f. 0. 



