[27] CEPHALOPODS OF NORTHEASTERN COAST OF AMERICA. 
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. 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 in- 
clined inward, those on the outer margin being largest. 
Among the loose sucker-rims there are some which differ from the 
others in having the rim more oblique, and the inner edge with nearly 
obsolete teeth. These suckers of the second kind differ from the cor- 
responding ones of A. princeps in having, on the outer margin, more 
numerous, more slender, and sharper teeth, which taper regularly from 
base to tip and are not so flattened. The larger of these sucker-rims 
(t) are 14.5" in diameter across the base; aperture, 9""; height at back, 
7™"; in front, 2°"; number of large denticles on outer margin, ten to 
fourteen; the inner margin, except in the smaller ones, is either finely 
toothed or distinctly crenulated, and there are usually one or more irreg- 
ular, broad, sharp lobes or imperfect teeth on the lateral margins. The 
teeth of the outer margin are regular, strongly incurved, tapering from 
the base to the very sharp tips, and sharply beveled on the edges. A. 
smaller one (j), 11™" across the base and 4.5™" across the aperture, with 
height of back 6", has five regular sharp teeth on the outer margin, 
two broad irregular ones on each side, while the front edge is nearly 
entire. These are supposed to come from the ventral arms. Others (h) 
are completely intermediate between the two principal forms, having 
very oblique rims, with a small aperture, but distinctly denticulate all 
around, the denticles on the inner margin being distinctly smaller than 
on the outer. 
Measurements of sucker-rims from short arms (in millimeters). 
a. b. Oo d. | | . 
(ale.) | (ale.) | (ale.) \(dry.)) f. |. 9: h. ie 
Diameter, outside, at base .......-...- 17 17 | 20 18 21 | 19 20.5 | 16 14,/5-|, 11 
Diameter of aperture.......-.-.......- 13 10 | 16 14 17 | 16 16.5 | 9.5} 9 4.5 
Height of horny ring, back side....... 7.5 9/ 8 7 | acc | Meine |e Sta ay / 6 
Height of horny ring, front side ...-... 3 Cal Nie ettass 3 Ci fe 3 3 2 1.5 
Number of distinct denticles..._-- L..-| 46 41 | 50 _ 49 50] 48 | 49 34 14 7 
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 
