REPORT OF COMMISSIONER OF FISH AND FISHERIES. [36] 
inches from front to back; breadth of its front or sucker-bearing surface 
(without the lateral membranes) is, where widest, near the base of the 
arm, .50 of an inch; the width gradually decreases to .18 of an inch at 
20 inches from the base; beyond this the arm tapers to a very slender 
tip, with numerous small, crowded suckers in two regular rows. At the 
base (Plate VI, fig. 4) there is first one very small sucker; this is suc- 
ceeded by two or three much larger ones, increasing a little in size; 
beyond these are the largest suckers, extending to about the 25th, 
beyond which they gradually change their form and regularly diminish 
in size to the tips. The larger proximal suckers, up to the 25th to 30th, 
are relatively broader than those beyond, and have a wider and more 
open aperture, and a more even and less oblique horny ring, which is _ 
sharply denticulate around the entire circumference, with the denticles 
rather smaller on the inner than on the outer margin, but similar in 
form. These are about .31 of an inch in external diameter. They show 
a gradual transition to those with more oblique rims and smaller aper- 
tures. Beyond the 30th the horny rims become decidedly more oblique 
and one-sided, with the denticles nearly or quite abortive on the inner 
side, and larger and more incurved on the outer margin, while the aper- 
ture becomes more contracted and oblique. At first there are eight to 
ten denticles on the outer margin, but these diminish in number as the 
suckers diminish in size, till at about 6 inches from the tip there are 
mostly but two or three, and the aperture is very contracted. Still 
nearer the tip there are but two blunt ones; then these become reduced 
to a single bilobed one; and finally only one, which is squarish, appears 
in the minute suckers of the last two inches of the tip. The first two or 
three suckers at the base of the arm are more feebly denticulated than 
those beyond, with smaller apertures. 
On many of the suckers (Plate IV, fig. 2 a) there are still remaining, 
in more or less complete preservation, a circle of minute horny plates, 
arranged radially, or transversely on the edge of the membrane around 
the aperture, similar in arrangement to those described in another part. 
of this article on the suckers of Sthenoteuthis pteropus (Plate XVII, fig. 
9). They are less developed, however, than in that species, being thin- 
ner and more delicate, nor do their ends appear to turn up in the form 
of hooks. They seem to be generally very thin, oblong, scale-like struct- 
ures, with rounded or blunt ends and slightly thickened margins. These 
structures will probably be found to vary with age, and perhaps with 
the season. They appear to be easily deciduous, and are often absent 
in preserved specimens, 
On the dorsal and third pairs of arms the suckers have essentially the 
same arrangement, form, and structure, and on these three pairs of arms 
the larger suckers differ but slightly in size. The character and arrange- 
ment of the suckers on the distal portion of these arms is well shown on 
Plate VI, figs. 3,3 a, which represent a portion of one of the third pair 
of arms, commencing at the 67th sucker. 
