CEPHALOPODS 469 
GENUS Argonauta 
A. argo. In this species, the paper-nautilus, the shell, which is pos- 
sessed only by the female, is not chambered. The animal rests in the 
shell, but has no or- 
ganic connection 
with it other than by 
the membranous ex- 
pansions at the ex- 
tremities of the two 
dorsal arms, which 
secrete it and hold it 
in place. The pur- 
pose of the shell is 
to hold and protect 
the eggs. 
Genus Loligo 
L. Pealei. In this Argonauta argo, side view of shell. 
species the body is 
cylindrical, tapers to a point, and has a fiat appendage in front. The 
fins are terminal, half, or more than half, as long as the body, united in 
a point posteriorly, and obtusely rounded on the outer angles. The 
head is a little narrower than the mantle. There are eight sessile, sub- 
triangular arms furnished with two series of 
suckers which are hemispherical and stalked, and 
two long retractile tentacular arms dilated at the 
extremities, bearing four rows of suckers. It has 
a pen- or quill-shaped cartilaginous substance in 
the dorsal integument of the mantle. Common 
from Cape Cod to South Carolina. 
L. brevis. A small short-bodied species, with 
short rounded caudal fins. It is common from 
South Carolina to Florida, and extends as far north 
as Delaware Bay. 
Genus Ommastrephes 
O. illecebrosus. <A species similar to L. Pealei, 
but with shorter fins. These are broad and pear- 
shaped, one third wider than they are long, and 
usually reach less than one half the length of the 
mantle. They are straight on the posterior end, 
and form nearly a right angle, while the upper 
margins are rounded. The head is as broad as the 
mantle. The arms are stout and taper to an acute 
point. The tentacular arms are long when ex- 
panded. The species is abundant from Cape Cod 
to Newfoundland, and is found ‘as far south as 
Newport, Rhode Island. This is the squid which is 
Loligo Peatei fe- : : : 
“aue6 Agen vie. used so extensively in the Banks fishery as bait. It 
