A. E. Verrill — North American Cephalopoda. 409 



bases of the arras. Eyes large ; lids thin and simple, without a dis- 

 tinct lachrymal sinus. Behind and below each eye there is a long 

 (4'"'"), slender, clavate, soft papilla (fig. 1/'), probably olfactory in 

 function. 



The sessile arms are large and, except the ventral, unusually round- 

 ed ; the inner sucker-bearing faces are much less differentiated than 

 usual, scarcely differing from the other sides iu color, and bordered by 

 only a slight or rudimentary membrane on each side ; the rounded 

 prominences tVom Avhich the sucker-pedicels arise are also colored and 

 not much raised. The dorsal arms are rather long and tapering, but 

 much shorter and smaller than the others, slightly compressed and 

 with a slight median crest distally. The next pair are similar in 

 form and structure, but considerably longer and larger. The third 

 pair are much longer and larger, with the outer angles well rounded, 

 and a strong median crest extends nearly to the base, but is wider 

 distally, where the arms are strongly compressed. The ventral arms 

 are considerably longer and stouter than the third pair, and very 

 diffei'ent from all the others in form; they are strongly compressed 

 in tlie direction parallel with the median plane of the head, and have 

 the low'er and outer angles well rounded, and the sucker-bearing face 

 wide and scarcely differentiated from the lateral faces ; but on the 

 superior lateral side there is a wide and thick crest running the 

 whole length of the arms, giving them a strongly and obliquely com- 

 pressed appearance. The suckers on the veutral arms are smaller, 

 fewer, and more distant than on any of the others; those at the bases 

 are largest and three or four stand nearly in a single row ; farther out, 

 along the middle of the arm, they are distantly arranged in two rows 

 and rapidly become small. The left ventral arm shows no signs of 

 being hectocotylized ; the right one, however, has lost half its length 

 by mutilation. On all the other arms the suckers are regularly and 

 much more closely arranged in two rows, and. decrease more gradu- 

 ally in size from near the base to the tips. 



The suckers on all the arms are similar in form ; they are rather 

 deep, narrowed at the rim, slightly constricted above the middle, 

 and swollen below, and very oblique at the base; the pedicels are 

 slender and nearly laterally attached ; the horny rims are very deep 

 and oblique, and strongly denticulated on the outer or higher side, 

 but on all the arms they are sm.ooth on the inner side; the median, 

 outer denticles are long, slender, close together ; laterally they become 

 shorter, broader, acute-triangular and curved forward. On the lai'ger 

 suckers the outer teeth are obtuse, but on the distal ones they become 



