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MOLLUSCA. 
Loligo vulgaris. — The Common Cuttle-Fish. 
Plate XCV. fig. 3. 
Wings somewhat rhomboidal, the bag cylindrical, and angular 
at the base; the sac limb three-lobed; the dorsal lamina ante¬ 
riorly narrowed. Inhabits the European seas. 
Genus 3—LOLIGOPSIS.— Lamarck. 
Generic Character. —Mouth terminal, surrounded by eight 
sessile and equal arms ; body fleshy, oblong, enveloped in a bag, 
which is pinnated behind, and slightly acuminate at the base. 
Genus 4.—O CT OPUS. — Lamarck. 
Generic Character. —Mouth terminal, surrounded by eight 
simple elongated arms, provided with sessile cups ; body fleshy, 
obtuse beneath, and enveloped in a bag, which is unprovided 
with wings; internal dorsal bone exceedingly small, or devoid 
of one in some species. 
Octopus vulgaris. —The Common Octopus. 
Plate XCV. fig. 5. 
Body smooth; cups arranged in double rows, and set some¬ 
what apart; arms tapering to an acute point. 
Sub-Division II. —Cephalopoda Monothalama. 
Having unilocular shells, entirely external, and enveloping the 
animal. 
Genus 5.—ARGONAUTA.— Linnaeus. 
Generic Character —Shell spiral, univalve, unilocular, and 
membranaceous ; doubly carinated. 
Argonauta Argo. —The Argus Argonauta, or Paper 
Nautilus. 
Plate LXXXIII. fig. 2. 
Shell white, involute, extremely fragile, sides with undulated 
ridges, and obsolately striate; keel with small tubercles. Inha¬ 
bits the Mediterranean. 
Sub-Division III.— Cephalopoda Polythalama. 
Shell mul til ocular, partly or wholly internal, and enveloped 
in the posterior part of the body. 
