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TEUTHIDiE. 



The squids and cuttle-fishes, commonly so called, be- 

 long to the Decapodous division of the Dibranchiate 

 Cephalopoda. The mollusks of this section have ten 

 arms, two of which differ in length, shape, and insertion, 

 from the rest, and are usually designated tentacula. The 

 suckers on these arms are stalked. The eyes are capable of 

 free motion. The siphon is usually provided with a valve. 

 In shape they are often elongated, and always furnished 

 with fins. Their shell is internal : in some it is a horny 

 pen ; in a few it is the body called cuttle-bone ; more 

 rarely it is a chambered shell, variously combined with 

 pen, or bone, or gourd. The Teuthida have variously 

 shaped bodies ; in the majority of species it is elongated, 

 with fins occupying a portion of the length ; their shell is a 

 horny pen, consisting of an axis, and more or less developed 

 side-wings. 



SEPIOLA. Leach. 



Body oval or rounded, short, united to the head by a 

 broad ligament, and furnished on each side with a subor- 

 bicularfin. Constricting apparatus at the base of the loco- 

 motive tube, and constituted of a pair of elongated furrows, 

 corresponding to linear crests on the inner wall of the sleeve. 

 Head short, but large, bearing ten arms, of which two are 

 tentacular and retractile. Eyes covered by an expansion 

 of epidermis. Pen corneous, flexible, small, blade-shaped. 



