CEPHALOPODS OF THE PHTLrPPESTE ISLANDS 137 



ventrally. For slightly less than half its length the mantle is cyhndri- 

 cal and nearly straight sided. Near the anterior margin of the fins 

 the mantle becomes abruptly narrower and tubular and continues so, 

 with straight sides, to some distance posterior to the fins. The gladius 

 is not visible for most of its length. 



The fins are thick and fleshy. In the larger specimens they are 

 longer than wide, but in the smaller specimen available to me they are 

 nearly round. They occupy more than 50 percent of the mantle 

 length and are joined together dorsally. Along the sides of the narrow 

 portion of the mantle extending beyond the fins are long thin bordering 

 membranes. 



The funnel is inconspicuous except at its extremity which is free. 

 The funnel member of the mantle locking apparatus is oval, with a 

 groove. Sasaki's description of the mantle member as shaped hke a 

 human nose is most descriptive. The funnel organ is composed of 

 two oval ventral pads and a broad V-shaped dorsal member. 



The head is long and narrow, less than one-third of the mantle 

 length, with large but deeply set eyes. The eyeUds are oval. The 

 head is deeply convex ventrally, so that the depth of the head exceeds 

 the width. There is no funnel excavation, and the neck is long and 

 slender. 



The arms are very unequal, with IV always the longest, in the order 

 4.3.2.1. IV is a httle longer than the mantle length. All the arms 

 are somewhat squarish in cross-section, concave on their oral surfaces, 

 convex on the aboral, and shghtly excavated on either side near the 

 sucker rows. All the arms except IV have protective membranes with 

 supports both dorsally and ventraUy. Ill is also equipped with a low 

 thick fleshy keel. The arms are bordered on the dorsal side by a low 

 thick fleshy web which extends the entire length of the arms. 



The suckers are biserial, subglobular, gradually becoming smaller 

 distally, and are smaUer throughout on the ventral arms. The 

 apertures are small and are on the lateral aspect of the suckers which 

 are raised on small slender peduncles. The horny ring is entire on the 

 proximal half and toothed on the distal half, the teeth between being 

 deeply cleft, squarish, and 9 to 16 in number. 



The tentacles are about twice as long as the mantle, and have long 

 slender stalks which are round in cross-section. The club is less than 

 one-third the length of the tentacle; the stalk becomes much more 

 slender and finally attenuate so that the club is very narrow. The 

 club, however, is bordered for its entire length on either side by a 

 broad protective membrane with numerous supports. The tentacular 

 suckers are somewhat cone-shaped and supported on their broad base 

 by long peduncles; the aperture of the sucker is on the proximal side 

 of the cone. The suckers are arranged in four rows, gradually de- 



