114 U.S. NATIONAL MUSEUM BULLETIN 234 



of the club. The hand is equipped on the ventral margin with six 

 long slender hooks of which the terminal ones are small and the third 

 from the base the largest. Each hook is accompanied dorsally by 

 two large, finely toothed suckers. The terminal portion of each club 

 is short, less than one-fourth of the total club length and bears four 

 rows of small nearly equal-sized suckers. 



The light organs are numerous and are found distributed over the 

 animal in three different sizes. Those on the ventral surface of the 

 mantle are numerous and are not arranged in any semblance of rows 

 except medially where two indistinct rows border a narrow clear 

 median zone or stripe. Elsewhere on the ventral mantle surface 

 minute, small, and large photophores are numerous, closely set but 

 becoming fewer and minute on the dorsal surface where only a few 

 widely spaced pairs are found. 



On the funnel are about 28 organs in four patches on the ventral 

 surface, with a line of four large photophores across the funnel in the 

 middle area. The dorsal bridles are equipped with light organs on 

 each side. 



There are five distinct rows of light organs on the ventral surface 

 of the head. The median row originates slightly anterior to the 

 funnel groove with a large photophore and extends forward with about 

 eleven organs, ending at the base of arms IV where it divides, each 

 branch forming a ventral row along the arms. The inner lateral row 

 originates posteriorly from two branches, one within the funnel 

 groove, the other on the inner nuchal fold. These unite at a large 

 organ on the posterior surface of the head and lead forward as a single 

 row to arm IV where it forms the middle row of the arms. The outer 

 lateral row originates on the second nuchal fold and leads forward in 

 a shallow arc with a break at the ventral "windows" of the eyes. 

 This row terminates between the bases of arms IV and III. Within 

 the funnel groove there is a single large white photophore posterior 

 to and slightly medial to the inner nuchal fold. There is a circlet 

 of about 30 light organs around each eyelid. 



The ventral arms bear three distinct rows of light organs. Of these 

 the ventral row extends to near the tip, the middle row extends to the 

 tip, and the dorsal row on the keel extends only to near the tip. On 

 the basal quarter of IV there are a few photophores, varying between 

 four and nine in a scattered row between the ventral and median 

 rows and one or two scattered organs near the base between the 

 median and the dorsal row. Arm III has a few widely spaced photo- 

 phores along the base of the keel on the ventral side and a few scattered 

 along the dorsal side. Arm II bears only a single basal organ. 



The eyeball bears six photophores on the ventral periphery. The 



