210 A. E. Terrill- — North American Cephalopoda. 
diameter. but though somewhat smaller than in the specimen just 
described, they have the same kind of denticulation around the 
margin. Their -mailer -ize may indicate that the specimen was a 
male, but they may not have been the largest of those on the arm. 
Arc hiten this princeps VeniiL 
Ar&ifcwtk&s f'-moefti VerrilL Am«. Joora. Science, voL ix. pp. 124. 181. Plate T, 
18!$; American Naturalist. toL ii. ppi !i T9, fig'? 
OwniifrrjAt'i (ArdutemOtu) primceps Try on. Alannal of Couchologj, p. 185, PL 85, 
1*78 figures copied aa4 description ocmpQed from papers or A. E. Y.). 
Plate ITU Plate XV ILL Plate XIX. Pl ate XX. 
T > S', ecies :- li-tinguishel by : he length and inequality of the 
short arms, of which the longest (ventral or sub vent ra 1 the 
combined length of the bead and body by about one-sixth ; by the 
denticulation of the ~uckers of the short arms, of which there are two 
principal form-, some having very oblique horny rings with the outer 
edge very strongly toothed and the inner edge slightly or imperfectly 
denticulated : the others having le— oblique rings with the denticles 
similar in :orm all around, though smaller on the inner margin ; by 
the stronger jaws, which have a deeper notch and a more elevated 
tooth •: the anterior edge : and by the caudal fin. which is short- 
sagittate in form, with the posterior end less acuminate than in the 
preceding species. 
This species wa- originally based on the lower jaw, mentioned as 
Xo. 1, and on the upper and lower jaws, designated as No. 10. in the 
first part of this article. The jaws of No. 10 were obtained from 
the stomach of a sperm whale taken in the North Atlantic, and were 
presented to the E-sex Ii -titute by Capt. N. E. Atwood, of Province- 
town, Mass., but the date and precise locality of tbe capture are un- 
known. The size and form of these jaws is well shown in Plate 
X VIII. fig-. 1, 2. Tbe total length of the upper jaw fig. l ) is 127" 
(5 inches) : greatest transverse breadth, 37- a ‘ (1*45 inches) ; front 
to back. -9 -- (3-5 inches); width of palatine lamina, (2*32 
inches). The frontal portion is considerably broken, but the dorsal 
portion remaining appears to extend nearly, but not quite, to the 
actual posterior end, the length from the point of the Wak to the 
posterior edge being -">'4 - (34 inches). The texture is firmer and 
the laminae are relatively thicker than in A. Harveyi. The rostrum 
and most of the frontal regions are black and polished, gradually 
becoming orange-brown and translucent toward the posterior border, 
and marked with faint -triae radiating from the tip of the beak, and 
