^Challenger'' Cephalopoda. 185 



then tapering posteriorly, and terminating in a blunt point. 

 The j^iw is more than half the length of tlie body, trapezoidal, 

 with rounded lateral angles ; the extreme breadth is less than 

 the length and is situated anteriorly to the middle of the tin. 

 The mantle-margin presents a triangular process in the mid- 

 dorsal line and is deeply sinuate ventrally. The siphon is 

 short and bluntly conical. 



The Head is short and not so broad as the body ; the eyes 

 are comparatively small and have a bracket-shaped auricular 

 crest behind and a minute pore in front of them. 



The Arms are unequal, the order of length being 3,4, 2, 1, 

 and, on the average, rather more than one third the length of 

 the body ; the first are the most slender, and have the dorso- 

 median angle raised into a prominent keel ; the second have 

 only a faintly-marked angle ventro-laterally ; the third have 

 a broad web externally, passing over at the base into one 

 which extends up the dorsal aspect of the lateral arms. The 

 suckers are arranged in two series, pedunculate, very oblique, 

 and rather larger on the lateral than on the other arms ; the 

 horny ring has about nine short, close-set, square-cut teeth 

 on its distal side, and is smooth on the proxinial. The hecto- 

 cotylus was not observed. The buccal membrane has five 

 points, each of which bears two or three small suckers ; 

 the two ventral points are rounded off ; just within the ventral 

 margin is a small papilla surrounded by two elevated rings, 

 probably for the reception of spermatophores. Both the outer 

 and inner lips are folded. 



The Tentacle is faintly three-sided and shorter than the 

 body, one third of its length being taken up by the club^ 

 which is expanded and triangular in section ; there is a pro- 

 tective membrane on either side and a web externally ; in the 

 centre are eight large suckers^ three times the diameter of the 

 lateral ones ; at the proximal end are about nine suckers, 

 gradually increasing in size, and at the distal end more than 

 twenty rows arranged in four series, gradually diminishing. 

 The largest suckers are scarcely at all oblique, and have the 

 margin cut up by radial grooves into a number of small 

 papilla, an arrangement also found on the outer margin of 

 the lateral suckers, but not in the terminal ones. The horny 

 rings of the largest suckers are smooth ; those of the lateral 

 bear about twelve long distant teeth on their outer margin ; 

 those of the terminal suckers are similarly armed. 



The Surface is smooth. 



The Colour is pinkish yellow, with purplish cliroraato- 

 phores. 



The Gladhis has not been extracted. 



