264 CEYLON PEAEL OYSTEK REPORT. 



tapers, 4 pectinate spines and a few long setae on the hind margin. Hand slightly 

 tapering, with 5 or G pectinate spines on the hind margin. Dactylus continuous 

 with the hand and about one-fourth as long, contracting to a curved point beyond 

 the middle (fig. 21. gn. 1 ). 



Second gnathopods are rather longer than the 1st ; the wrist has 4 pectinate 

 spines on the distal half, of which the 2nd and 3rd are longer than the others and 

 have a shorter spine at the base. 



First and 2nd perasopods are much shorter than the gnathopods, the 1st joint as 

 long as all the rest ; 3rd, 4th, and 5th subequal. Dactylus small and curved, with a 

 seta in the middle of the front margin ; a curious strong curved spine rises from the 

 distal end of the anterior margin of the 5th joint and appears to duplicate the 

 dactylus (fig. 21. pp. 1 ). 



Remaining pernaopods are alike ; the 1st joint oval ; the 3rd much longer and wider 

 than the subequal 4th and 5th, which have the anterior margin spinous and minutely 

 pectinate. Dactylus with a supplementary point. 



First uropods extending beyond the 2nd, rami shorter than the pediincle, subequal 



Second uropods extending a little beyond the end of the peduncle of the 3rd, outer 

 ramus the shorter. 



Third uropods : rami narrow, lanceolate, considei'ably longer than the peduncle, 

 subequal in extent ; the outer spinous on the distal half of the outer margin and with 

 a central row of spines ; the inner with the tip truncate and emarginate, with a spine 

 at each angle (fig. 21. up. 3 ). 



Telson not quite reaching the end of the 3rd uropods, cleft almost to the base, the 

 divisions pointed, tips spinous, a submarginal spine near the distal end of the inner 

 margins (fig. 21. up. 3 ). 



Superficially very like T. acanthurus, Lillje., but differs in the single dorsal tooth 

 instead of the serrate hind margin of the pleon segments, and in the structure of the 

 maxillipeds, gnathopods, antennular apjiendage, 3rd uropods, &c. 



Eusiroides, Stebbing, 1888. 

 Eusiroides caesaris, Steb. var. Plate IV., fig. 22. 



Various localities round Ceylon. 



Agrees with the type except as regards the pleon segments, which are not dorsally 

 produced, and the 3rd has the hind margin only slightly convex, with but 3 teeth on 

 the lower third part ; the posterior angle is a rounded right angle (fig. 22. pi. 8 ). 

 The telson is divided more than half its length. 



Length of female with ova 8 millims. 



Eusiroides orchomenipes, n. sp. Plate IV., figs. 23. 



In a tube marked " Cheval Paar, February, 1902," with 2 large normal specimens 

 of the last form, was an ovigerous female 5 millims. long. This has the entire hind 



