CTTELXJlirDJE. 285 



1. Icilius ellipticus. (Plate XLVII. fig. lU.) 

 Icilius ellipticus, Uaiia, U. S. Explor. Expcd. p. 844. pi. oG. f. 4. 



** Cephalon short, broad, triangular, front and side angles obtuse, 

 Pcrcion oval ; first segment narrow and very short. Pleon seven- 

 jointed; three anterior segments at the middle of the posterior 

 margin acutely prolonged. Eyes very remote. Antennae sub- 

 terete : inferior longer than the body ; flagellum about t"\vice as 

 long as the base, verj' slender : superior nearly half shorter ; 

 flagellum not t'v^dce as long as the base. Gnathopoda densely 

 hii-sute on the inner or anterior side of the last two or three 

 joints. Three posterior pairs of pereiopoda similar; the fifth 

 much longer than the fouilh. Telson small, ovate. 



** Length 2 lines. 



" Balabac Passage, north of Borneo ; brought up on corallines in 

 31 fathoms." — Dana. 



Fam. 4. CHELURID^. 



This fiimily was founded by Professor Allman for the reception of 

 a single species. The Cheltjrid^ are distinguished from the Coro- 

 iMiiiD-K by the fusion together of several segments of the pleon, and 

 by the abnormal character of the three posterior pairs of pleopoda 

 of the only species known. 



1. CHELUEA. 



Clu'lura, Philippi, Wlcgmann's Archii; 1839. 

 Allman, Ann. Nat. Hist. xix. p. 3G1. pi. 13. 



Superior antenna) ha\-ing a multiarticulate flagellum, and carrying a 

 secondarj- appendage ; inferior antennas much longer than tlie 

 superior, very robust and powerful, having the flagellum with all 

 the articidi fused together. Mandibles with an appendage ; max- 

 illipeds ungiuculate. Gnathopoda chelate, sube(iual. Pereiopoda 

 short, subecjual. Penultimate iiaii* of pleopoda having the i)eduncle 

 developed into a squamose plate supporting two rami ; iiltimate 

 pair unibranched. Telson single. 



1. Chelura terebrans. (Plate XLVIII. fig. 1.) B.M, 



Clielura terebrans, I'Inlippi, Wiegmami's Archii; 1839. 



Allman, Ann. Nat. Ilist. xix. p. 13. 



Spcnre Bate, Urit. Assoc. Report, 1855. 



White, Hist. Brit. Crust, p. 202. 



Gossc, Marine 7,ool. \. p. 1.38. f. 250. 

 Nemertes ne.saioides, White, Cut. Crust. B. M. 1847. 



Male. — Third segment of the pleon armed with a large ccutro-dorsal 



