ISOPODA OF THE 'LIGHTNING' AND OTHEE EXPEDITIONS. 81 



Diagnosis of Species of Apseudes here described. 



No rostrum, front truncate obtusifrons. 



Rostrum minute, simple, a mere point. 



Epistoma furnished with a spine ialpa. 



Epistoma not furnished with a spine. 



Second gnathopods with an ordinary curved dactylus latreillii. 



Second gnathopods with a curiously twisted dactylus uncidigitatus. 



Rostrum long, acute, with a bulb-like swelling on each side of the base. 

 Bulbs convex in front. 



Carapace with a pair of large lateral spines gracilis. 



Carapace without lateral spines. 



Hand of second gnathopods ovate, not much longer than broad . spinosus. 

 Hand of second gnathopods elongated, hnear, 3-4 times as long as 



broad simplicirostris. 



Bulbs concave in front lunarifrons. 



Rostrum tridendate, composed of three acute processes grossimanus. 



Besides the foregoing species, four other forms have recently been recorded by 

 Prof. G. O. Sars from the Mediterranean — Apseudes tenuimanus, acutifrons, robustus, 

 and echinatus. The last certainly comes very near to, and may prove to be identical 

 with, the Apseudes lunarifrons. A species has also been described by Studer from 

 Kerguelen Island, Apseudes spectabilis (vStuder, ' Isopoden der Eeise S.M.S. ' Gazelle ' 

 urn die Erde, 1874-76,' 1884, p. 23, pi. i. fig. 9, a-g). 



1. Apseudes talpa (Montagu). 

 Cancer (Gammarus) talpa, Montagu, Trans. Linn. Soc. ix. p. 98, pi. iv. fig. 6. 

 Apseudes talpa, Leach, Edinb. Encyclop. vii. 1814, p. 404 ; id. Trans. Linn. Soc. xi. p. 372 ; id. Suppl. 



Enc. Brit. i. p. 428 ; Samouelle, Entom. Compend. p. 109 ; Lamarck, Hist. Nat, Anim. sans 



Verteb. (deuxieme ^dit.) v. p. 290 ; LatreUle, Enc. Method, pi. cccxxxvi. fig. 26 ; Cuvier, Reg. 



Anim. edit. LatreUle, pi. cliv. p. 124 ; edit. Crochard, Crust, pi. xlii. fig. 1 ; id. Anim. Kingdom, 



edit. Henderson, iii. p. 223, pi. xxxvi. fig. 4; Guerin, Icon. pi. xxvii. fig. 6; Lucas, Hist. Nat. 



des Crust, p. 243; Milne-Edwards, Crust, iii. p. 140; White, Brit. Mus. Cat. Brit. Crust. 



p. 67 ; id. Pop. Hist. Brit. Crust, p. 226 ; Gosse, Marine Zool. i. p. 136, fig. 245 ; Bate and 



Westwood, British Sessile-eyed Crust, ii. p. 148 ; G. O. Sars, Revision af Gruppen Isopoda 



Chelifera, 1880, p. 10. 

 ? Eupheus ligioides, Risso, Crust, de Nice, 1816, p. 124, pi. iii. fig. 7 ; Hist. Nat. de TEurope Merid. 



V. p. 99 ; Desmarest, Consid. gen. Crust, p. 285 ; Milne-Edwards, Crust, iii. p. 142. 

 Eupheus talpa, Desm. Consid. gen. Crust, p. 285. 

 ? Apseudes ligioides, Lucas, Hist. Nat. Crust, p. 243 ; Lamarck, Anim. sans Verteb. (2" edit) v. 



p. 291. 



Rostrum triangular, acute. Ocular alse obtuse. Eyes well developed. Segments 

 of peraeon narrower than carapace, each having a short triangular process at the latero- 



