50 U.S. NATIONAL MUSEUM BULLETIN 234 



pairs of suckers ; the other suckers are in four rows, the marginal rows 

 bearing suckers almost imperceptibly larger than those of the inner 

 rows. The most notable feature of this species is the small, nearly 

 equal suckers on III which are so strikingly different from those of 

 the other arms. On IV, the suckers of the inner rows are nearly 

 minute, but the outer rows bear about eight greatly enlarged suckers 

 about three or four times the size of the inner ones. DistaUy there is an 

 abrupt decrease in size, but even distally the suckers of the outer 

 rows are larger than those of the inner ones. The enlarged suckers 

 on aU the arms are about the same diameter and have a Sis of 5.3-5.9 

 in contrast to a Sis of 2.5-3.3 in the females. 



In the male the left dorsal arm is hectocotylized by the modifica- 

 tion of the suckers of the distal half. Basally there are about 35 

 normal suckers of which two, located a quarter of the length of the 

 arm from the base in the ventral row, are modified into long fleshy 

 papillae. Beyond this proximal half, the suckers are modified into 

 short fleshy papillae surmounted at the extremity by a slitlike aper- 

 ture, with fleshy lips. These modified suckers are in four rows, the 

 two pairs of rows being turned outward. In the larger male there is 

 a broad expanse between the two sets of rows, but in the smaller 

 ones this clear area is reduced or absent. Ventrally, the papillae 

 form a closely packed palisade, less so dorsally. There are about 68 

 papiflae crowded into the distal section. Aborally a broad keel is 

 highly developed over the modified section. 



Measurements and indices of six specimens of Euprymna alba- 

 trossae Voss, 1962, from Catanduanes Island are: 



The tentacles are short and stout, flattened orally, angled on the 

 dorsal side. The clubs are small, only slightly expanded and bear 

 about 20 rows of very minute suckers. There is a broad stout dorsal 

 web. 



The color is yellowish with numerous large purplish-brown chro- 

 matophores, which are numerous both dorsally and ventraUy on the 

 head, mantle, and arms. The fins are heavily pigmented over most 

 of the dorsal surface and bear a large central patch of spots on the 



