SEPIA OFFICINALIS. 



THE SECONDARY CHARACTERS. 



SEPIA. Body contained in a sac, bordered throughout its 

 length by a narrow fin, and inclosing in the back a shell 

 formed of an infinity of very small, fine, calcareous laminae. 

 Mouth surrounded with ten arms, of which two are much 

 longer than the rest, and have suckers at the extremity only. 



THE SPECIFIC CHARACTERS. 



SEPIA OFFICINALIS. Arms small, with serrated cups. Ten- 

 tacula two, longer than the arms. Mouth in the centre of the 

 arms, horny, hooked like the bill of a hawk. 



NATURAL HISTORY. 



The CUTTLE-FISH, also called the Ink-fish (from the juice 

 which the animal ejects, and which was used as ink by the 

 ancients), is of an oblong form, about six inches in length and 

 three and a half in breadth. The body is somewhat oval, but 

 it is broadest near the head, and grows smaller towards the 

 extremity, where it is obtusely pointed. The head is divided 

 from the sac on all sides by a neck. The sac is furnished 

 on each side, throughout its whole length, with a narrow fin. 

 The suckers are irregularly scattered on the arms and feet. 

 The back is strengthened by a complicated calcareous plate, 

 which plate has been long known in the stores of the apothe- 

 cary under the name of Cuttle-fish bone, and was formerly 

 much prized in medicine as an absorbent, but is now chiefly 

 sought after for the purpose of polishing the softer metals. 

 The superior half, or the one next the head, is the longest, 

 rounded at the extremity, and thin. The inferior portion be- 

 comes suddenly narrow, and ends in a point. .It may be con- 

 sidered as consisting of a dormal plate, concave on the central 

 aspect, having its concavity filled up with layers which are 

 convex on their central aspect. The dormal plate consists of 

 three different lamina?, arranged parallel to one another. The 

 external or dorsal layer is rough on the surface, and marked 

 by obscure concentric arches towards the summit, formed by 

 minute knobs, which become larger towards the base, where 

 they appear in the form of interrupted transverse ridges. It 

 is uniform in its structure, and the tubercles possess a polish 

 and hardness equal to porcellaneous shells, although they 

 blacken speedily when put in the fire, and contain a good 

 deal of animal matter. On the central side of this layer is 



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