Species of Maioid Crustacea. 21 



concave interspaces between the regions, and covered with 

 small conical acute tubercles; the spines of the lateral margins 

 are conical and scarcely longer than those of the surface of the 

 body. Rostrum very small, acute, with a spine on each side 

 of the median one ; interocular space smooth, concave. An- 

 terior legs greatly elongated ; arm spinulose above and on its 

 anterior margin ; on the posterior margin are seven longer 

 spines, alternating with smaller ones ; wrist minutely tuber- 

 culate above, and with six or seven alternately larger and 

 smaller spines on its posterior margin ; hand spinulose or 

 tuberculate above, its anterior margin with fifteen to eighteen 

 compound or branching spines, which increase in size towards 

 the distal extremity, posterior margin with five to eight 

 longer, alternating with smaller spines ; under surface of arm 

 and wrist nearly smooth, of hand minutely granulated or 

 tuberculate. Spinules of the merus joints of the ambulatory 

 legs very small. Penultimate joint of the postabdomen of the 

 male armed with a spine or tubercle. Length of an adult 

 male to base of rostrum f inch ; breadth 1 inch. 



Hob. Eastern Seas; Javan Sea {H.M.8. l Samarang ') ; 

 Dunk Island {J. Macgillivray r , Esq., H.M.8. 'Rattlesnake') ; 

 Isle of France ( Old Collection) . 



I have described this species at length because, although it 

 is probably the species intended by M.-Edwards in his short 

 diagnosis of L. longimanus, it is possibly not the Cancer 

 longimamcs of Linnaeus. I may here note that the specimens 

 in the British Museum from India, Singapore, and the Philip- 

 pines, referred by White (' List Crust. B. M.' p. 11) to Lam- 

 bras longimanus, appear to belong to Lambrus affinis y A. M.- 

 Edwards. This latter species has evidently a very wide 

 range, and may perhaps be identical with the long-pre- 

 viously described L. pelagicus, Ruppell, as it differs only in 

 the smoothness of the arms on the front part of their upper 

 surface, and in the greater prominence of some of the tuber- 

 cles on the posterior (outer) margin of the hand ; and speci- 

 mens of both varieties are in the British Museum from Zan- 

 zibar. 



b. Merus joints of the ambulatory legs not armed with spines or 

 distinct tubercles. 



Lambrus dejlexifrons, sp. n. (PI. V. fig. 5.) 



The carapace is strongly constricted behind the orbits, with 

 the cardiac region very convex, and with an oblique but 

 shallow sulcus on the branchial regions, and is covered with 

 closely-set small tubercles ; the antero-lateral margins are 



