312 MOLLUSCA. 



Sepia, Lam. 



The Sepiae, properly so called, have the two long arms of a Loli- 

 go, and a fleshy fin extending along the whole length of each side of 

 the sac. The shell is oval, thick, convex, and composed of nume- 

 rous and parallel calcareous laminae, united by thousands of Utile 

 hoUoAv columns, running perpendicularly from one to the other. 

 This structure rendering it friable, causes it to be employed for po- 

 lishing various kinds of workj it is also given to birds in aviaries, 

 for the purpose of whetting their beaks. 



The ink-pouch of the Sepiae is detached from the liver and situ- 

 ated more deeply in the abdomen. The glands of the oviducts are 

 enormous. The eggs are produced attached to each other in branch- 

 ing clusters resembling those of grapes, and are commonly termed 

 sea-grapes. 



The species most commonly found in the seas of Europe, 

 Sepia officinalis, L.; Rondel., 498, Seb., Ill, iii, attains the 

 length of a foot and more. Its skin is smooth, whitish, and 

 dotted with red. 



The Indian Ocean produces another. Sepia iuberculata. Lam. 

 Soc. d'Hist. Nat., 4to, pi. i, f. 1(1). 



Nautilus, Lin. 



In this genus Linnaeus united all spiral, symmetrical and chambered 

 shells, that is to say such as are divided by septa into several cavi- 

 tiesj their inhabitants he supposed to be Cephalopoda. One of them, 

 in fact, belongs to a Cephalopode that strongly resembles a Sepia, 

 but it has shorter arms — it forms the genus, 



Spirula, Lam. 



In the hind part of the body, which is that of a Sepia, is an inte- 

 rior shell, which, although very different from the bone of that ani- 

 mal as to figure, differs but little in its formation. A correct idea 

 of the latter may be obtained by imagining the successive laminas, 

 instead of remaining parallel and approximated, to be concave to- 

 wards the body, more distant, increasing but little in breadth, and 



(1) Small bodies, armed with a spine, are frequently found among Fossils — they 

 are the extremities of the bones of Sepiae. They constitute the genus Belop- 

 TEHA, Deshayes. See my note on this subject, Ann. des Sc. Nat. II, xx, 1, 2. 



There are some other — but petrified — Fossils, which appear to be closely allied 

 to the above bones. They are the Ryncholithes of M. Faure Biguet. See Gail 

 lardot, Ann. des Sc.Nat., II, 485, and pi. xxii, and of Orbigny, lb., pi. vi. 



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