CEPHAI^OPODA OP THP HAWAIIAN ISLANDS. 
329 
A. is a remarkably distinct species and is not closely approached by any other known form 
excepting possibly the very recently described A. steindachneri Weindl 1912 of the Red Sea, which 
is thought by its author to be somewhat nearly related. A complete account of the latter species has 
not yet reached me, but from the preliminary notice above cited it would seem that this is the case, 
although the two forms differ in enough particulars to be sufficiently distinct. In Weindl’s species 
the fins are not quite so short and wide, there are seven to eight hooks on the tentacle club, and the 
median photophore on the eyeball is said to be much the smallest. 
It has seemed worth while to make the account of this species as full as possible, firstly on account 
of the special interest attaching to forms of this group, and secondly because of the unusually fine 
condition of the present specimen which renders the chance for misinterpretation correspondingly 
slight. 
Abralia trigonura Berry 1913. 
Abralia species Berry 1909, p. 419 (locality record only). 
Abralia trigonura Berry 1913, p. 565. 
There is a second specimen of Abralia in the Albatross collection, which, although not very well 
preserved, is clearly not referable to A . astrosticta, but belongs rather to the typical section of the genus. 
Animal of small size, in general loliginiform, but the mantle rather short, wide, inflated, and 
rapidly tapering to a point posteriorly. Fins large, a little over 
half as long as the mantle; their total width about approximates 
the length of the mantle. 
Head rather small, squarish; olfactory crests low (crushed, and 
not distinct). Eyes large and prominent. Funnel large, trian- 
gular, compressed. Funnel organ well developed; similar in general 
arrangement to that of A. astrosticta, except that the lobes of the 
median (dorsal) pad are broader, and the ventro-lateral cushions 
are ovate and conspicuously larger (fig. 33). The funnel has a 
delicate foldlike valve at the tip. 
Arms quite long, over two-thirds the length of the body; sub- 
equal, but the dorsal pair distinctly the shortest; order of length 
in general 2, 4, 3, i. The arms bear two rows of small alternating 
hooks, which are replaced by suckers at the extremities. 
Tentacles very long and slender, the clubs little expanded, 
effaced, but a single hook persisting on one of the clubs is much longer, more slender, and much more 
curved than those of A. astrosticta. 
Buccal membrane large; eight-pointed; papillose and imiformly pale within; its outer surface 
conspicuously dotted witli many small, distinct, dark reddish chromatophores. 
The gladius as compared with that of A. astrosticta is similar in general shape, but is relatively 
much flatter and less slender, with, however, a wider and more robust midrib; the lateral expansions 
are conspicuously broader and their angles more pronounced and more anterior in position. 
The photophores of the ventral integument are of a very different aspect than those of A . astrosticta, 
but here also they are apparently of two main types. The larger appear as small whitish tubercles, 
which, under the microscope, show a lenslike core of chalky white color inclosed by a pale bluish 
gray ring. The smaller organs are either (i) conspicuously darker, comprising a light bluish core 
surrounded by a narrow dark ring distinctly composed of separate bodies of pigment, or (2) but slightly 
darker and resembling the large organs in miniature. The integument of the mantle has mainly 
sloughed away, but from the portions remaining there appear to have been two very definite parallel 
rows of the larger organs running down the medio-ventral line, with at least two other series on either 
side more or less parallel to them . The smaller organs are exceedingly numerous and heavily distributed 
among the larger all over the ventral stuface. 
Fig. 33 . — Abralia trigonura, outline draw- 
ing of funnel organ [275], X 3- 
The armature is almost entirely 
