384 



IDOTEID^. 



ISOPODA. 



NORM ALIA. 



IDOTEIBjF.. 



IDOTEA. PELAGICA. 



Specific character. Front of the cephalon slightly notched ; lower antennw 

 about one-third of the length of the animal, which is narrow, but with the 

 middle segments rather widest. Pleon with the first two joints distinct, the 

 third with the sides only distinct, united with the fourth in the middle ; 

 fourth joint large, with a slight keel down the middle, rounded at its ex- 

 tremity, with a small blunt tooth in the middle. 



Length, half an inch, 



Jdotea pelagica. Leach, Trans. Linn. Soc. xi. p. 365. Suppl. Enc. Brit. 



i. 426. Desmarest, Cons. Crust, p. 289. Samotjelle, 



Ent. Comp. p. 106. Milne Edwards, Crust, iii. p. 129. 



White, B. M. Cat. Brit, Crust, p. 65. Pop. Hist. 



Brit. Crust, p. 223. 

 Idotea marina. Fabricius, Ent. Syst. Suppl. p. 303 ? 

 Oniscus halthicus. Pallas, Spic. Zool. ix. t. 4, f. 6 ? 

 Bhcetia pelagica. Leach, MSS. 



Our figures of this species are drawn from Dr. Leach's 

 largest typical specimen in the British Museum Collec- 



