82 U.S. NATIONAL MUSEUM BULLETIN 234 



Description. — The mantle is long and slender, about one-sixth to 

 one-seventh as wide as long, tubular, and tapering posteriorly to 

 a slender point. The anterior margin is produced dorsally into 

 a distinct lobe, the ventral portion emarginated with lateral projec- 

 tions on either side of the funnel. 



The fins are large, occupying nearly two-thirds of the mantle 

 length and widest anterior to the midpoint with slightly convex 

 anterior margins and strongly concave posterior margins. 



The head is small, compact, with large eyes. The ventral surface 

 is deeply excavated for the funnel. 



The funnel is stout, strong, and reaches about to the midpoint 

 between the eyes. The funnel organ is indistinct. 



The arms are short, in the order 3.4.2.1, I distinctly the shortest, 

 strongly keeled for the entire length, and strongly compressed. II is 

 not keeled but is angled on the dorsal surface and equipped with 

 a broad swimming membrane ventrally. Ill is stout, longer than 

 the others, compressed and bears a swimming membrane on the 

 aboral surface. The protective membranes on III are much deeper 

 than on the others and exceed the depth of the suckers. IV is 

 bordered by a membrane on the dorsal edge and has a slight keel on 

 the ventral edge. The sessile suckers are biserial. The suckers are 

 somewhat barrel-shaped, the pedicels inserted obliquely. The aper- 

 tures are slightly pointed distally. The horny ring is smooth on the 

 proximal half but bears seven to nine long slender teeth on the distal 

 side, the anterior ones being longest and reducing in size gradually 

 towards the smooth portion of the border. 



The left ventral arm is hectocotylized by the modification of the 

 distal half of the sucker-bearing portion of the arm. Proximally 

 there are 15 pairs of normal suckers of the same size as those of the 

 right ventral arm, but much smaller than those of I-III. Beyond 

 the 15th pair of suckers, the pedicels are greatly enlarged and elon- 

 gated, especially those of the ventral row and bear at their tip a small 

 fleshy sucker without a horny toothed ring. There are about 33 of 

 these pedicels of which the distalmost seven or eight are extremely 

 minute and without suckers. 



The tentacles are long and somewhat slender, compressed, with 

 a slight groove on the distal oral surface. The club is short, only 

 slightly expanded, with a trabeculate protective membrane bordering 

 each side. Aborally there is a keel extending the length of the club. 

 The tentacular suckers are quadriserially arranged, the median two 

 rows of the hand about a fourth larger than those of the lateral rows. 

 The horny rings are surrounded by a narrow papillated area. The 

 rings of the large rhachial suckers bear 20 to 22 sharp curved teeth 



