378 CEYLON PEARL OYSTER REPORT. 



ovigerous female) in the bottle which contains Pocock's " type" specimen of 

 Hyastenus (Ckorilia) tenuicornis, labelled " China Sea." 



The interesting little tooth of the supra-orbital margin is referred to under 

 H. irami, n. sp. 



Halimus pehlevi, n. sp. Plate I, fig. 3, 3a. 



Localities : Coral reefs, Gulf of Manaar, two specimens ( f\ g) ; pearl banks, Gulf 

 of Manaar, 15 specimens. One is a young female; six are adult females (five are 

 ovigerous) ; five are young males ; five are adult males. 



Description of Adult Male (g). Carapace sub-triangular, globular behind the 

 lateral post-hepatic groove. The regions are distinctly defined, and are convex 

 independently of the general convexity of the carapace, and bear certain granules : 

 a pair at the anterior border of the gastric region internal to the bases of the supra- 

 ocular eaves ; 13 posterior to these on the gastric region, of which three are median ; 

 one (median) between the gastric and cardiac regions ; thi'ee on the cardiac region 

 arranged as a triangle with its base turned forward ; one (median) intestinal ; one in 

 the posterior portion of the groove on either side of the cardiac region ; two on each 

 branchial region. The true posterior border of the carapace is convex apart from the 

 general outline of the carapace. The rostral spines are divergent, the distance 

 between their tips divided by the length of one of them = I'll. Length of rostral 

 spine (inner border) -f- carapace length = 0*39. The spines are bordered laterally with 

 hooked hairs. The supra-ocular eave is strongly bilobed ; the post-ocular tooth has a 

 denticle about the middle of its anterior border. The pterygostomian region bears a 

 couple of tubercles, one to outer side of and behind the other. 



The antero-external angle of the basal antennal joint is produced into a stout tooth 

 which is just concealed in a dorsal view of the animal. Behind it the outer border of 

 the basal joint of the antenna presents a slight convexity which is produced ventrally 

 a little. Posterior to this and external to the opening of the green gland is a 

 prominent laterally compressed tubercle, and posterior to this again the antero-external 

 angle of the buccal cavern forms a prominence. The four prominences just named 

 form a longitudinal row. The antennal flagellum does not reach so far forward as the 

 tip of the rostral spine ; it is stout and bears a few thick hairs averaging somewhat 

 more than 0"5 millim. in length. 



The merus of the external maxilliped lias its antero-external angle produced, and 

 its inner border indented by two notches. The inner border of the ischium of the 

 same appendage is serrated. 



Chelipeds are smooth beneath the hairs. In this adult male they are a little stouter 

 than the walking legs and 1*2 times as long as the carapace (excluding rostral spines). 

 The fingers gape proximally for about two-thirds of their length, a tooth on the 

 proximal portion of the mobile finger projecting into the hiatus. The distal, apposable 

 portion of the ringers is denticulate. 



