REPORT OF COMMISSIONER OF FISH AND FISHERIES. [28] 
vary greatly according to the state of contraction or relaxation. The 
length given (24 feet) probably represents the extreme length in an ex- 
tended or flaccid condition, such as usually occurs in these animals soon 
after death. The slender portion is nearly three-cornered or triquetral 
in form, with the outer angle rounded, the sides slightly concave, the 
lateral angles prominent, and the inner face a little convex and gener- 
ally smooth (Plate I, fig. 1, e e.) 
The terminal portion, bearing the suckers, is 76.2 in length and ex- 
pands gradually to the middle, where it is 11.4 to 12.7 in cireumfer- 
ence (15.3 when fresh) and 3.9” to 4.1™ across the face. The sucker- 
bearing portion may be divided into three parts. The first region (i to 4 7) 
occupies about 17.8” (7 inches); here the arm is rounded-triquetral, 
with margined lateral angles, and gradually increases up to the maxi- 
mum size, the inner face being convex and bearing about forty irregu- 
larly scattered, small, flattened, saucer-shaped suckers, attached by very 
short pedicels, and so placed in depressions as to rise but little above 
the general surface. The larger ones are 5" to 6™" in external diameter ; 
3™ across aperture; 1.5°™ high. The smaller ones have a diameter of 
4™™: aperture, 2.5"; height,1™". The horny ring (Plate IV, Figs. 9, 9a) 
is circular, thin, and of about uniform breadth all around; the edge is 
smooth and even, slightly everted ; just below the edge there is a groove 
all around; below this a prominent, rounded ridge surrounds the pe- 
riphery, below which the lower edge is somewhat contracted. A thick, 
soft membrane surrounds the edge. These suckers are at first distantly 
scattered, but become more crowded distally, forming six to eight irreg- 
ular alternating rows, covering the whole width of the inner face, which 
becomes 4.1™ broad. Scattered among these suckers are about an equal 
number of low, broad, conical, smooth, callous verruce, or wart-like 
prominences, rising above the general surface, their central elevation 
corresponding in form and size to the apertures of the adjacent suckers. 
These, without doubt, are intended to furnish secure points of adhesion 
for the corresponding suckers of the opposite arm, so that, as in some 
other genera, these two arms can be fastened together at this wrist-like 
portion, and thus may be used unitedly. By this means they must 
become far more efficient organs for capturing their prey than if used 
separately. The absence of denticulations prevents the laceration of 
the creature’s own flesh, which the sharp teeth of the other suckers 
would produce under pressure, and the verruce prevent the lateral 
slipping, to which unarmed suckers applied to a smooth surface would. 
be liable. Between these smooth suckers and the rows of large ones 
there is a cluster of about a dozen small suckers, with sharply serrate 
margins, from 5™" to 8"" in diameter, attached by slender pedicels. They 
are arranged somewhat irregularly in four rows, those of the outer 
rows more oblique, and corresponding in form with the larger marginal 
suckers. 
The second division (ii to iii), 35.6 in length, succeeds the small suck- 
