MOLLUSCA. 
340 
surface, and as it has been even asserted that the germ of this shell has been seen in the egg of the 
Argonaut *, we must say that this opinion is, to say the most of it, still very problematical. — Poll, 
Testae. Neap. hi. p. 10. See also Ferussac, Mem. de la Soc. d'Hist. Nat. de Paris, ii. p. 160 ; and 
Ranzani, Mem. di Star. Nat. Lee. i. p. 85. It is the Nautilus and Pompilus of the ancients. — Plin. ix. c. 29. 
We know some species, very like each other both in the animal and shell, which Linnaeus confounded together 
under the name of Argonauta argo, vulgarly called the Paper -nautilus. 
It is supposed that we must ascribe to an animal analogous to the Argonaut, the Bellerophon, shells 
rolled up spirally and symmetrically, and without septa ; but thick, not grooved, and whose last whorl is propor- 
tionably shorter. [Sowerby says that Bellerophon is the only fossil that bears any real resemblance to Argonauta, 
but neither shell, in his opinion, has been formed by a Cephalopodous animal, but probably by one nearly like 
that of Carinaria. The fossils are characteristic of the carboniferous limestone, and the oldest secondary strata : 
in these the shell is frequently found changed to silex.] 
The Sleeve-fish {Loligo, Lam.) — 
Have in the back, instead of a shell, a horny lamina in the shape of a sword or lancet. Their sac has 
two fins ; and besides the eight feet, furnished with small pedicled suckers inordinately arranged, their 
head supports two arras much longer than the feet, and only acetibuleferous near the ends, which are 
enlarged. These the animal employs as anchors to fix itself. Their ink-bag is buried in the liver ; 
and the glands of their oviducts are very large. They lay their eggs attached together in straight 
garlands, and in two series ; [and the entire mass somewhat resembles a mop, being composed of 
numerous intestine-like filaments tied together in the centre]. 
The family is now subdivided from the number and armature of the feet, and the form of the fins. The LoU- 
gopsis, like the Octopus, has only eight feet, but our knowledge of the genus rests upon figures that are scarcely 
trustworthy.t In Loligo properly so called, the arms have suckers as well as the feet, and the fins are situated 
towards the end of the sac. We have three species in our seas,— the L. vulgaris {Sepia loligo, Linn.) ; L. sagittata, 
and L. subulata, or Sepia media, Linn. The Onychotheuthis, Lichenst. {Onykia, Lesueur,) have the form of the 
Loligo, but the suckers of their arms end in hooked spines. The Sepiola have rounded fins, attached, not to the 
end, but to the sides of the sac. The common Sepiola (Sepia sepiola, Linn.) occurs in our seas. The body is short 
and obtuse, with small circular fins. It never exceeds three inches in length ; and its horny lamina is slender and 
pointed like a needle. :j: The Sepiotheutes, Blainv. (Chondrosepia, Leukard,) have the sac margined throughout 
with the fins, as in the Sepia ; but their shell is horny, as in the Loligo. 
The Cuttle-fish, strictly so called {Sepia, Lam.), — 
Possess the two long arms of Loligo, and a fleshy fin stretched along each side of their sac. Their 
shell is oval, thick, tumid, and composed of an infinity of very thin parallel calcareous laminae, joined 
together by thousands of little hollow columns, which are placed upright in the spaces between every 
two laminae. This structure renders it friable, whence it is employed by artists in polishing various 
works ; and it is given to cage birds to sharpen their beaks upon. The Sepia have the ink-bag separate 
from the liver, and situated deeper in the abdomen. The glands of the oviducts are enormously large. 
They deposit their eggs attached to one another in branehed clusters, not 
unlike a cluster of grapes, whence the vulgar have called them Sea-grapes. 
The species distributed in all our seas (Sepia officinalis, Linn.) reaches a foot or 
more in length. Its skin is smooth, whitish, and dotted with red. In the Indian 
Ocean there is one with a skin roughened with tubercles (S. tubercidata, Lam.). 
(Among fossils we find some little bodies armed with a spine, which are the 
ends of a bone of Sepiae. They constitute the genus Beloptera of Deshayes. See 
Ann. des. Sc. Nat. ii. xx. 1, 2. Some other fossils, but petrified, appear to have great 
relation to the beaks of the Sepiae. These are the Ry7icholithes of M. Faure Biguet. 
—See Gaillardot, Ann. Sc. Nat. ii. 485, and pi. xxii. ; and D’Orbigny, ib. pi. vi.) 
Linnasus united in one genus— his m.-E^gs of the Argonaut. 
Nautilus — 
All spirally twisted, symmetrical, and chambered shells, — that is to say, divided by partitions into 
several cavities ; and he supposed them to he inhabited by Cephalopods. One of them is, in fact, the 
shell of a Cephalopod, very similar to a Sepia, but with shorter arms : it is the genus 
Spirula, Lam. — 
In the hinder part of the body of the Cuttle is an interior shell, which, however dissimilar to the 
bone of the Sepia in figure, does not differ much from it in the manner of its formation. If we imagine 
i 
f 
II 
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a 
ii 
II 
a 
u 
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* This appears now to have been disproved. — Kd. 
t Loligopsis is now ascertained to iiave two arms, remarkable for 
their great length and gracility. — See Ferussac, in /Inn. des Sciences 
Nat. Part. Zool. n. s. iii. p. 339, &c. — Ed. 
t On tiic anatomy of Sepiola and Loligopsis, consult Ur. Grant’s 
paper in the 1st vol. of the Zoul. Trans . — Ed. 
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