' Challenger ' Cephalopoda. 225 



The Arms are unequal, the ventral considerably shorter 

 than the dorsal and dorso-lateral, on an average six times as 

 long as the body, stout and tapering very rapidly towards 

 the ends. The umbrella reaches up one fifth of the length of 

 the dorsal arms, and is a little wider between the lateral and 

 a little narrower between the ventral arms. The suckers are 

 not closely packed and not enlarged on the dorsal arms, not- 

 withstanding the sex of the specimen. The hectocotylized 

 arm is very short, but the modified extremity is long and 

 narrow, with parallel sides tapering only at the extremity to 

 a blunt point ; a narrow fillet runs between the two marginal 

 ridges. 



The Surface of the body is sprinkled dorsally with minute 

 hemispherical warts, which become smaller and gradually 

 disappear on the sides and lower surface ; they are also found 

 on the dorsal surface of the head and of the umbrella. Above 

 each pupil stands a small cirrus, immediately behind which 

 is a larger one. 



The Colour is a dull red on the dorsal surface, lighter and 

 brighter below, sprinkled with dull reddish-brown dots. 



Hob. The Hyalvnema-gvound south of Japan, 345 fathoms 

 (Station 232). One specimen, $. 



Octopus ton ganus , n. sp. 



The Body is rounded, depressed, and broader than long, 

 with a marked but shallow median groove on the ventral 

 surface. The mantle,' opening extends about one third round 

 the circumference of the body, terminating nearer to the 

 funnel than to the eye. The siphon is short and conical, and 

 extends rather more than halfway to the umbrella-margin. 



The Head is small and the eyes prominent. 



The Arms are unequal, the order being 3, 2, 4, 1 ; on an ave- 

 rage they are nearly ten times as long as the body, and taper 

 gradually to very fine points. The umbrella is very small 

 and slightly narrower dorsally than laterally. The suckers 

 are for the most part small and closely packed, the first four 

 are arranged in a single row ; in the male there are four large 

 ones on each lateral arm opposite the margin of the umbrella, 

 beyond which they gradually diminish. The hectocotylus is 

 very minute. 



The Surface is in general smooth ; the back bears a few 

 small papillae, but owing to the compression of the specimens 

 it is impossible to make out their exact number. There are 

 three minute cirri over each eye. 



The Colour is on the whole grey, paler below ; this is due 

 to dark specks sprinkled more or less closely over a cream- 



