68 U.S. NATIONAL MUSEUM BULLETIN 234 



Marinduque, grey mud and sand, in 165 m., Mar. 2, 1909; USNM 

 575343. 



Description. — The mantle is cylindrical, moderately stout, taper- 

 ing in its posterior haK to a blunt point. The dorsomedian area of 

 the anterior margin is produced as a small lobe. Ventrally the margin 

 is emarginated below the funnel, with pointed angles on each side. 



The fins are large, rhombic in outline, with straight anterior margins 

 sharply rounded laterally, and with concave posterior margins. The 

 fins are about half the mantle length, slightly larger in the females. 



The funnel is stout, reaching beyond the line of the eyes. The 

 locking apparatus is normal, the funnel member slightly curved, 

 pointed anteriorly and rounded posteriorly. The funnel organ is of 

 the usual type and large. The valve is large, semicircular, and 

 subterminal. 



The head is large, with prominent eyes. It is dorsoventrally flat- 

 tened. There is a prominent olfactory crest below and behind the 

 eye and a small pore between the eye and the arms near the base of 

 the 3rd arm. 



The arms are of moderate length, in the order 3.4.2.1. I is com- 

 pressed and keeled along its entire length. II is squarish with a 

 prominent ridge on its outer ventral margin. Ill is flattened, broad, 

 with a broad swimming membrane on its outer surface, widest about 

 in the middle. IV is again squarish, with a tentacular sheath mem- 

 brane dorsally and a keel ventrally. The suckers of all arms are 

 biserial and bordered on both sides by trabeculate protective mem- 

 branes. The arm suckers are of medium size, a little larger on the 

 lateral arms in the males. The horny rings bear on the distal border 

 about six to eight, usually seven, long square-cut teeth, the lateral 

 one or two on each side often as much as twice as broad as the median 

 ones. Proximally, the ring is smooth on the edge, but in a few cases 

 the edge may be irregular, but there is always an abrupt change from 

 the smooth proximal half to the toothed distal half. The aperture is 

 nearly one-half closed off by the broad platelike extension of the inner 

 margin of the horny ring in the proximal half. The suckers of the 

 ventral arms are much smaller than those of the other arms. 



In the males, the left ventral arm is hectocotylized for over two 

 thirds of its length. Basally there are about eight pairs of normal 

 suckers followed by 33 to 36 pairs of large fleshy pedicels, cone-shaped, 

 surmounted by tiny ringless suckers. The pedicels of the ventral 

 row are much longer than those of the dorsal row. 



The tentacles are long and slender, their stalks compressed, and 

 they bear large expanded clubs. The stalk is slightly keeled aborally 

 and flattened orally. There is a broad swimming keel on the aboral 



