341 



the preceding genus, with the palp smaller. Maxillae and maxillipeds nearly 

 as in tliat genus. Gnathopoda slender, and of much the same appearance as 

 in Aceros. The 2 anterior pairs of pereiopoda very largely developed, with 

 the joints, in parts, much expanded, and the dactylus very large and foliaceous. 

 The 2 succeeding pairs much smaller, and rather feeble in structure, with 

 the basal joint scarcely expanded. Last pair of pereiopoda well developed, 

 and of the usual structure. Uropoda and telson normal. 



JieiiiarJcs. — The present new genus is established to include the ano- 

 malous form described by the author, at an earlier date, as Halicreion lafipes. 

 Tlie affinity of the latter form to the genus Halicreion of Boeck is, however, 

 very slight, and it comes in, reality, much nearer to the genus Acerof^, to 

 which it also was referred by Dr. Hansen under another specific name. From 

 that genus, the present one is chiefly distinguished by the cephalon having 

 a distinct though small rostral projection, moreover by the very diiferent 

 structure of the superior antennae, the less strongly developed mandibles, 

 and finally by the structi;re of the pereiopoda, the 2 anterior pairs of which 

 are highly remarkable by their iinusualy robust form. The genus comprises 

 as yet but a single species, to be described in the sequel. 



33. Aceroides latipes, G. 0. Sars. 



fPl. 120, fig 2). 



HaUcreion latipes, G. O. Sars, Oversigt af Norges Crustaceer, I, p. 97, PI. 4, fig. 10. 



Syn.; CEdiceros obtusus, alia forma, Goes. 



,, Aceros distingvendus, Hansen. 



Body not very slender, and less tumid than in Aceros i)hyUonyA\ with 



the anterior segments of mesosome rather short. Cephalon about the length 



of the first 3 segments of mesosome combined, iipper face slightly vaulted, 



rostral projection very small, but acute, lateral lobes of cephalon rather broad, 



and somewhat emarginated at the tip. First pair of coxal plates obliquely 



quadrangular in form, and scarcely at all expanded distally; 2nd pair rather 



small, and somewhat narrowed distally; 3rd pair nearly as broad as the 2 



preceding pairs combined, and somewhat emarginated at the tip; 4th pair 



much lower than the corresponding segment, and but little diifering in size 



and form from the 3rd; 5th pair more than twice as broad as they are deep, 



and having the posterior lobe larger than the anterior. Eyes wholly absent. 



Superior antennae in female about the length of the cephalon and the first 



5 segments of mesosome combined, 1st joint of the peduncle fully as long as 



the other 2 combined, flagellum very fully developed, and nearly twice as 



long as the peduncle, being composed of about 12 artionlations, each having 



44 — Crustacea. 



