A, E. Verrill— North American Cephalopods. 201 
margins are largest, flat, lanceolate, with sharply bevelled lateral 
edges and acuminate tips; those on the front margin are shorter, 
narrower, acutely triangular, and in contact at their bases. On the 
largest of these suckers there are forty-eight to fifty denticles. Some 
of the suckers of rather smaller size (a, 6,) are more oblique, with the 
outer side of the horny rings relatively wider and more incurved; the 
denticles of the outer margin are strongly incurved and decidedly 
narrower and more acute than the lateral ones, which are broad- 
triangular; the “inner or front denticles are rather smaller, acute- 
triangular, and usually inclined somewhat inward. On these there are 
forty to forty-six denticles. No suckers of this specimen have been 
found with the denticles rudimentary or wanting on the front edge, as 
is frequently the case in those of A. princeps. Nor is there so much 
contrast in the form and size of the inner and outer denticles of the 
largest suckers as in that species. The rings of the smaller suckers 
are still more oblique and more contracted at the aperture than those 
of the larger ones, with the teeth more inclined inward, those on the 
outside margin being largest. 
Measurements of suckers of short arms (millimeters). 
a (ale.) b (ale.) ce (ale.) a (dry.) 
Transverse diameter, outside, _-_--- Wy 17 20 18 
Diameter of aperture,__-.....-_--- 13 10 16 14 
Breadth of horny ring, back side,-__ 75 9 8 7 
Breadth of horny ring, front side,-_. 3 3 3°5 3 
Number of distinct denticles, --__-_- 46 41 50 49 
The two long tentacular-arms are remarkable for their slenderness 
and great length when compared with the length of the body.’ Mr. 
Harvey states that they were each 731°5°" (24 feet) long and 7°™ 
(2°75 inches) in circumference when fresh. In the brine and alcohol 
they have shrunk greatly, and now measure only 411°5°™ (13°5 feet) 
in length, while the circumference of the slender portion varies from 
5°7™ to 7°25™ (2°25 to 3°25 inches). These arms were evidently 
highly contractile, like those of many small species, and consequently 
the length and diameter would vary greatly according to the state 
of contraction or relaxation. The length given (24 feet) probably 
represents the extreme length in an extended or flaccid condition, such 
as usually occurs in these animals soon after death. The slender 
portion is nearly three-cormered or triquetral in form, with the outer 
angle rounded, the sides slightly concave, the lateral angles promi- 
nent, and the inner face a little convex and generally smooth. 
TRANS. CONN. AcCAD., VOL. V. 26 JANUARY, 1880, 
