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SEPIADiE. 



The animal of the only genus of this family, of which 

 existing species are known, is a Decapod, having a broad 

 body, surrounded by a pair of narrow fins of nearly equal 

 dimensions throughout. The characteristic distinction of 

 the group lies in the shell, or cuttle-bone, which is a calca- 

 reous plate terminating in a more or less distinctly cham- 

 bered extremity. There are several fossil genera belonging 

 to the Sepiada, all, however, of tertiary age, though 

 species of the typical genus, Sepia, date far back, even to 

 the oolitic epoch. 



SEPIA. LlNN.dE us. 



Body oval, often very broad, compressed and depressed, 

 margined throughout its circumference by two narrow fins. 

 Locomotive apparatus formed of an oblong, conical crest, 

 bordered above by a deep circular furrow, and placed on 

 the inner wall of the sleeve, and of an oblong, deep, mar- 

 ginated furrow at the lower part of the funnel. Head 

 flattened, eyes covered by an epidermic expansion, pierced 

 with a small hole. Arms, ten, two of them tentacular, in 

 great part webbed together. 



Internal shell lodged dorsally, as long as the body, solid, 

 depressed, more or less oval, rounded and thin anteriorly, 

 bordered behind and often rostrated at the extremity ; 

 rugose above, bordered by a horny margin. 



