374 DE. W. T. CALMAN ON JJEW OE EAEE 



The remaining legs are subequal in length, and stout. The merus is slightly 

 inflated and about twice as long as the carpus ; the propodus is half as long as the 

 carpus and about equal to the dactylus, which is slender, curved, and terminates in a 

 curved claw-like spine. 



The uropods have the peduncle longer than the last somite and more than 

 one and a half times as long as the telson, slightly thickened distally where the 

 diameter is about one-third of the length. The exopod is nearly as long as tlie 

 peduncle. It bears two unequal setae at the tip and one or two small setules on the 

 outer and inner edges. The endopod is a little longer than the exopod. It is composed 

 of two segments, the distal a little longer than the proximal ; it has two unequal 

 spines at the tip and one spine on each segment on the inner edge. 



Adult Male. — Total length 1"9 mm. 



The carapace is more than one-third of the total length and has the dorsal outline 

 more arched than in the female. The pseudorostrum is shorter and truncated. The 

 antero-lateral serrations could not be demonstrated. The pleural plates of the third 

 leg-bearing somite are not expanded, and there is no marked interval between the 

 second and third pairs of legs. 



There are four segments in the outer flagellum of the antennules. The antenme 

 are very short, only reaching, in the natural position, to the posterior edge of the 

 carapace. There are well-developed exopods on the third maxillipeds and on all except 

 the last pair of legs. 



The peduncle of the uropods is about twice as long as the telson, and has four 

 spinules on the inner edge. The rami are nearly equal in length and their terminal 

 spines are long and slender. The endopod has, on the inner edge, two spines on the 

 tirst and three on the second segment. 



Memarks. — Apart from the presence of exopods on the third and fourth pairs of legs 

 in the male, this species is distinguished from G. carinata, which it resembles iu 

 general characters, by the more numerous ridges on the carapace, by the curved claws 

 of the posterior legs, and by other small characters mentioned above. 



(9c'c?<rmic^.— Gulf of Siam, " Koh Kam, 20 fathoms, 4/2/00," "N. of Koh Chuen, 

 15 fathoms, 5/2/00," " Between Koh Mesan and Cape Liant, 5-8 fathoms, 7/2/00." 

 Th. Mortensen Coll., Copenhagen Museum. Co-types in British Museum. 



Gynodiastylis bicristata, sp. n. (Plate XXXVI. figs. 11-22.) 



Bescription of adult Female. — Total length 19 mm. 



Carapace a little less than two-fifths of total length, its vertical height about two- 

 thirds of its length, inflated ; dorsal outline, as seen from the side, strongly arched 

 posteriorly, sloping in front. Pseudorostrum short, horizontal, acutely pointed as seen 

 from the side, truncated as seen from above. Antennal notch open, defined by a 

 triangular antennal tooth. The dorsal surface of the cai'apace has a pair of strong 

 cristiform ridges, which, starting from the hind margin, diverge anteriorly and then 



