252 PERCY SLADEN TRUST EXPEDITION 



Female. — Tomentose, with a few longer hairs. A tubercle on the branchial margin 

 at the widest part of the carapace ; two granules on the anterior part of the branchial 

 region, 1 on the hepatic margin, five on the gastric region. Horns slender, strongly 

 divergent, inclined downward, slightly curved, nearly as long as carapace (in middle line). 

 Supra-ocular eave with a distinct but small anterior spine, outer margin oblique, almost 

 straight. Anterior edge of postocular cup straight. Antennal spine scarcely visible in 

 dorsal view. Antenna reaching about | of length of rostrum. A spine at distal end of 

 arm and of merus joints of legs ; dactyli of legs spinulous. 



Dimensions in mm.: ?, C. 1. med. 8, C. b. 5-2, R. 1. 6. $, C. 1. med. 4-8, C. b. 3'2, 

 R. 1. 4-2. 



219. Halimus uncifer (Caiman) (Plate 20, fig. 7). 



Hyastenus uncifer Caiman, Proc. Zool. Soc. London, 1909, p. 712, pi. 72, figs. 8, 9. 



Diego Garcia, 12 fins.; 1 $. 



Thinly tomentose. Carapace subpyriform, regions well defined, areolated. A stout 

 curved intestinal spine, a smaller curved spine on the branchial margin and a small straight 

 spine on the hepatic margin. On the gastric region two median tubercles and in a curved 

 line with the anterior one 4 other tubercles; on the branchial region two tubercles arranged 

 longitudinally, the posterior one in transverse line with the marginal spine, the anterior 

 one has a granule in front of it. 



Rostral horns very slender, about 1^ times as long as carapace, well separated at base, 

 slightly curved, nearly horizontal, their middle third beset with curled hairs. Interorbital 

 space with 3 deep grooves. Supraocular eave oblique, anterior angle spiniform, posterior 

 angle tuberculiform and widely separated from the shallow postocular cup. Basal joint 

 of antenna with an antero-external spine, outer margin sinuous ; flagellum not reaching 

 middle of horn. Pterygostomian region trispinose, middle spine smallest. 



The chelipeds reach beyond middle of rostrum, are moderately stout ; arm and wrist 

 each with a distal spine, three spines on outer surface of wrist ; palm increasing distally, 

 2f times as long as wide ; fingers gaping in basal half, where there is a large tooth on the 

 dactyl, and the immovable finger is arched. The merus joints of the legs bear a stout tooth 

 at their extremity ; and the dactyli are armed with unusually long and very conspicuous 

 spines, which are directed proximally. 



Horns marked with 3 or 4 broad bands of colour. 



Dimensions in mm.: C. 1. med. 9'S, C. b. inch spines 6'5, R. 1. 12. 



This species in its few protuberances and length of horns resembles H. brockii de 

 Man*, but the carapace is less ovate, the postocular lobe more transverse, while the rake- 

 like dactyli of the legs are unique. 



220. Halimus tenuicornis (Pocock). 

 Hyastenus tenuicornis Alcock (1), p. 215. 



Cargados Carajos, 30 fins., Sta. B 3; 1 ? ovig. : 20—25 fms., Sta. B 17 ; 1 $. 

 Salomon ; 1 $ juv. Egmont, reef; 1 $ juv. Amirante, 29 fms., Sta. E 2 ; 2 $, 1 $ ovig.: 



* Arch. f. Naturg., liii. 1887, p. 221, pi. 7, fig. 1. 



