Indian Deep-sea Dvedyincj. 281 



the antennules, its basal toothed portion almost horizontal, its 

 apical portion lon^r, slender, styliform, straight, and ascen- 

 dant : the first tooth arises just at the Icv^cl of tlie supraorbital 

 margin, its ridge extending as a shar|)ish and diminishing 

 dorsal crest nearly to tiie hinder edge of the carapace ; the 

 second arises about the length of an eye-peduncle from the 

 first, and the tliird about half that distance from the second. 

 A long postorbital crest commences close behind the orbital 

 margin, and extends without interruption to the gastro- 

 hepatic groove, where it ends, to reappear again in the interval 

 between the gastro-he))atic and cervical grooves ; the crest of 

 the antennal spine is short, extending only to the antennal 

 groove ; the long crest of the branchiostegal spine runs hori- 

 zontally backwards as far as the curved cardio-branchial 

 ridge and groove, which with it demarcates the upper boun- 

 dary of the subjacent branchial chamber ; below the branchio- 

 stegal crest a ridge of nearly the same strength delimits the 

 indurated superior from the membranous inferior part of the 

 sides of the carapace and anteriorly runs to the anterior 

 margin, while posteriorly it is continuous with the raised rim 

 of the posterior margin on each side. 



The legs are slender and weak. 



A tine female from Station 112, 5G1 fathoms. 



Colour in life bright orange. 



The specimen was strongly luminous when first brought on 

 board. 



16. Aristceus ci'assipes, sp. n. 



Body pubescent. Rostrum long, extending by fully one 

 half of its length beyond the peduncles of the antennules; 

 its basal toothed portion slightly descendant, its apical portion, 

 which is excessively slender and styliforra, ascends in a faint 

 curve to its excessively fine and sharp point ; the first tooth 

 arises well to the rear of the orbital margin, the second about 

 the length of an eye-peduncle from the first, and the third 

 about two- thirds of that distance from the second ; the crest 

 of the first extends backwards as a blunt dorsal ridge to about 

 midway between the cervical groove and the hinder margin 

 of the carapace ; a blunt postorbital crest defines the antennal 

 groove superiorly, and an almost equally blunt short crest to 

 the antennal spine limits it below ; the crest of the branchio- 

 stegal spine is somewhat stronger and sharper than in the 

 preceding species, but presents similar relations to the cardio- 

 branchial groove, at its junction with which a groove passes 

 off obliquely downwards and backwards towards but not up 



Ann, & Mag. N. Hist. Ser. 6. Vol. viii. 19 



