CEPHALOPODA OF THE HAWAIIAN ISLANDS. 



331 



Fins relatively enormous, 



at the tips of all the arms, as in Abralia, except the ventral pair which bear only hooks; extremities of 

 ventral arms with a conspicuous series of heavily pigmented black bead-like organs probably photogenic 

 in function. Left ventral arm hectocotylized, but distinguished chiefly by its very wide web with 

 broad lappets at the margin ; no glandular swellings. Two rows of suckers on proximal portion of tentacle 

 club suppressed in adult, leaving either two rows of hooks or one row of hooks and one row of suckers, 

 which give way distally to four rows of suckers. Buccal membrane deep violet in color. Photogenic 

 organs of the mantle usually showing a definite bilateral arrangement; three rows of these organs present 

 on the lower aspects of the ventral arms, two occurring on the arm itself, the other upon its marginal 

 web. A single series of five large photophores occurs upon the ventral periphery of the eyeball, the 

 terminal organs of this series being somewhat larger than the remainder. 



Type. — Enoploteuthis Hoylei Pfeffer 1884 (designation); described from the Mascarene Islands. 



Abraliopsis species (young). 



Abraliopsis species Berry 1909. p. 419 (mere locality record). 



Animal small. Mantle short, acutely conical, widely flaring in front 

 over two-thirds the length of the mantle and notably wider when 

 taken together than the latter is long, anterior lobes prominent and 

 angular. 



Head small ; only broader than long because of the large conspic- 

 uous eyes. Funnel flattened, little projecting. 



Arms rather long, very slender and attenuate ; decidedly unequal, 

 their formula 4, 2, 3, 1; the ventral arms conspicuously longer than 

 the others, the dorsal pair notably the shortest. Armature consisting 

 of two alternating series of small elevated hooks, the latter persist- 

 ent nearly to the tips of the arms, so that the usual suckers at the 

 extremities are very small and obscure and have not in the present 

 case been actually observed by me. 



Buccal membrane eight-pointed; its coloration violet through- 

 out except for the paler and more whitish trabecular. 



Photogenic organs of mantle conspicuous and exhibiting a very 

 definite grouping, not even the smaller ones being very irregularly 

 scattered; on the ventral surface of the mantle occur six very definite 

 rather distant converging series, with traces of another row as repre- 

 sented by three or four widely spaced organs lateral to these. On the 

 head three conspicuous rows (the only ones shown in the figure) with 

 another weaker row lateral to these and a rather weak circle around 

 the eyelid opening, making seven rows in all. Along the ventral 

 aspect of the ventral arms there are two rows and one row on the 

 third pair. 



The ventral arms bear at their extremities a bead-like series of 

 three distinctly separate smooth black ovoid swellings, the median one notably the largest. 



The subocular organs are yellowish in color but too badly damaged to be made out very clearly 

 Color in alcohol a brownish buff; the chromatophores darker but comparatively few in number 

 Photophores bluish with paler centers. 



L 



Fig. 34. — Abraliopsis sp., young, ventral 

 view [276], X 2. Drawn by R. L. 

 Hudson. The representation of the 

 photogenic organs is incomplete. 



Measurements of Abraliopsis species (young). 



Total length exclusive of tentacles 35 



Length of mantle, dorsal x6 



Extreme length of fins u 



Length of fins at base 9 



Width across fins 19 



Width of mantle near anterior margin 7 



Width of head 6 



mm. 



Length of — 



Head 5 



Dorsal arm 7 



Second arm 12 



Third arm 11 



Ventral arm is 



Funnel 5 



