of the ''Challenger'' Expedition. 419 



with about five delicate spines. Clielipedes very slender, 

 furnished with rows of spinules, the ambulatory limbs with 

 spatulate tarsi. Abdominal segments smooth and glabrous. 



Length of body (of a ? with ova) 15 millim. j length of 

 ■ chelipedes 32 millim. 



Log. Station 192 [off the Kai Islands], 129 fathoms. 



DiPTYCHUS, A. Milne-Edwards. 

 Diptychus, A. Milne-Edwards, I. c. p. 61. 



Diptychus insignis^ n. sp. 



Rostrum long, slightly upturned, with two or three minute 

 lateral teeth towards the apex. Eyes minute. Carapace 

 with a row of small spines in front, extending across the 

 gastric and hepatic regions, the remainder of its surface smooth 

 and glabrous : the lateral border furnished nearly as far as its 

 posterior termination with small spines, of which the first and 

 those corresponding to the ends of the gastro-hepatic row are 

 largest. Chelipedes robust, the raeral and carpal joints 

 strongly tuberculate and armed with several prominent spines. 

 Ambulatory limbs with the tarsi short and strongly toothed, 

 the inferior margin of the propodal joints produced distally 

 and furnished with spines. 



Length of body (of a cJ ) 32 millim. j length of chelipedes 

 44 millim. 



Lac. Station 145 [off Prince Edward Island], 310 fathoms. 



Dijptychus spinimarginatus, n. sp. 



Rostrum almost straight, long and narrow, the borders with 

 two or three minute teeth towards the apex. Eyes minute. 

 Carapace narrowed anteriorly, sparingly clothed with delicate 

 hairs, especially towards the sides, the posterior half of the 

 lateral borders armed with five large spines and a few smaller 

 in front of these. Chelipedes long, slender, and cylindrical, 

 the carpal and propodal joints smooth and about equal in 

 length. Ambulatory limbs with the upper border of the 

 meral joints spiny, the first pair very slender. 



It is allied to D. armatiis, A. M.-E., but in the latter the 

 carapace is armed laterally with seven or eight spines, and 

 the ambulatory limbs are smooth. 



Length of body (of a ? wnth ova) 21 millim. ; length of 

 chelipedes 29 milJim. 



Log. Station 170 [off the Kermadec Islands], 520 fathoms ; 

 station 214 [off the Philippines], 500 fathoms. 



29* 



