CEPHALOPODA. 
465 
hatched in this floating cradle. Three species are at present known : 
| e species described by Aristotle and Pliny, and the more ancient na- 
urahsts; namely, A. argo, or Nautilus poupyracea (Figs. 319 and 320), 
^'hich are inhabitants of the Mediterranean as well as the Indian 
cean and the Antilles. The two others, A. tuhercula, belonging 
delusively to the Indian Ocean, and A. haillant, which is "met 
occasionally in the Pacific and Atlantic Ocean. 
The poulpes and nautilus both belong to the family of Octopoda, and 
the class of Acetabuliferous Cephalopoda, having, as the name indicates, 
ei ght feet, from oatw, eight, and n rou?, foot ; at the same time the body 
entirely fleshy, and without fins. The genera of Cuttles (Sepia) and 
Calmars (Lolia) belong to another family of the same class ; namely, the 
Oecapoda, because they have ten feet and a sort of internal osselet 
^ith fins, &c. 
The cuttles, Sepia (Fig. 323), have the 
tody fleshy and depressed, continued into a 
Sa<; , and bordered on all its length on both 
Sl des with a wing or narrow fin, the larger 
s tort and flat, broader than it is long, with 
t' v ’o large eyes, covered by an expansion of 
the skin, which becomes transparent over a 
^arfaee equal to the diameter of the iris, and 
tarnished with inferior contractile eyelids. 
This head is surmounted by ten tentacular 
arms or feet, eight of which are short and 
e °nieal, and two long and slender, terminat- 
es in a sort of spatula. These arms are 
armed with suckers, and are perfectly retractile. They surround 
4 mouth armed with two horny jaws not unlike the beak of a parrot. 
The skin of the cuttle-fish presents in one vast hollow, occupying all 
„ e extent of the back, a great calcareous part, the form and structure 
° which is quite characteristic of this genus. It is known as the 
mtle-bone (Fig. 324). This bone is used for many purposes ; 
4 mong others, it is used in a powdered state as a dentifrice. It is 
8 °metimes suspended in the cage with captive birds, that they may 
bet their beaks on it, and collect carbonate of lime for the formation 
atl 4 repair of their bones. The osselet is oval or oblong, some pro- 
Fig. 323. Sepia officinalis (Linnaeus). 
