108 U.S. NATIONAL MUSEUM BULLETIN 234 



when the arms are brought together. The hooks and suckers are 

 bordered on either side by a low membrane of about equal depth with 

 short but stout supports. 



The hooks of the arms are large, narrow, and strongly arched with 

 long, narrow, curved distal tips. 



The tentacles are short. The stalks are flattened, rectangular in 

 cross-section with strongly angled corners. The inner ventral angle 

 is composed of a strong muscle at the base which, in the pocket 

 formed by III and IV, separates and passes downward and attaches 

 at the base of IV as part of the brachial crown base. ' In the space 

 between this muscle and the stalk another muscle originates near the 

 base of arm IV and, passing dorsaUy, attaches to the brachial crown 

 near the base of arm III. 



The tentacular club is moderately expanded, broad in the proximal 

 part but rapidly tapers to a narrow tip which curls ventrally. Prox- 

 imaUy there is a carpal cluster which in the left club has four cups and 

 four(?) buttons, but in the right there are five cups and four buttons. 

 Distad of the carpal cluster is a minute hook on the ventral edge of 

 the club, followed by five others on the left club of which the 2nd, 

 3rd, and 4th increase in size, the latter the largest of all, the 5th 

 and 6th decreasing somewhat. Each hook has a pair of large, 

 minutely toothed suckers at its base, representing apparently the 

 two dorsal rows, the inner ventral row having been lost. Distad of 

 the hooks the club terminates in an area bearing four rows of minute 

 suckers. On the dorsal border the club bears a protective membrane 

 which originates opposite the 1st hook just above the carpal pad and 

 terminates opposite the base of the 6th hook. On the outer surface 

 of the club opposite the base of the 3rd hook a strong broad swimming 

 membrane originates. This membrane lies adjacent to the base of 

 the protective membrane, borders the distal section of the club, and 

 encircles the distal suckers. The right tentacular club bears only 

 five hooks, the 6th apparently being missing. 



The light organs, as in other Ahralia, are numerous and conspicuous. 

 They are found both dorsaUy and ventraUy upon the mantle, sparsely 

 on the funnel, and in distinct rows on the ventral surface of the head, 

 the ventral periphery of the eyebaU, and the ventral and ventrolateral 

 arms. Although the specimen is in an excellent state of preservation, 

 some of the features of the light organs are no longer discernable but, 

 by their size, they appear to be of three lands, minute, smaU, and large. 

 They are arranged as follows on the body: 



On the ventral surface of the mantle they are placed thickly, the 

 large Ught organs numerous and conspicuous and arranged somewhat 

 in rows, longitudinally. There is a clear stripe on the midventral 

 line which is followed on either side by a row of all three types of 



