432 



CEPHALOPODA. 



the lower surface of every one of the eight flexible arms. If the 

 Poulpe but touch its prey, it is enough : once a few of these tena- 

 cious suckers get firm hold, the swiftness of the fish is unavailing, 

 as it is soon trammelled on all sides by the firmly holding tenta- 

 cula, and dragged to the mouth of its destroyer ; the shell of the 

 lobster or of the crab is a vain protection, for the hard and crooked 

 beak of the Cephalopod easily breaks to pieces the frail armour ; 

 and even man himself, while bathing, has been entwined by the 

 strong arms of gigantic species, and struggled in vain against a 

 grasp so pertinacious. 



(475.) In the genus Octopus the arms are only eight in num- 

 ber, and nearly of equal length ; but to the Calamaries (Loligo) 

 and other genera an additional pair is given, which, being pro- 

 longed considerably beyond the rest, are not merely useful for seiz- 

 ing prey at a distance, but become convertible to other purposes, 

 and may be employed as cables whereby the Cephalopods so fur- 

 nished ride securely at anchor in a tempestuous sea ; the suckers 

 being placed upon an expanded disc situated {Jig. 214) at the 

 extremity of the elongated tentacula, and thus rendered capable of 

 taking firm hold of the surface of a rock or other fit support. 

 The posterior extremity of the body is in such forms generally 

 provided with two broad muscular and fin-like expansions {Jig. 

 214), evidently adapted to assist in sculling the animal along. 



Wonderful as are the provisions above described for insuring 

 food and safety to these formidable inhabitants of the sea, it is 

 only by an attentive examination of the individual suckers, so 

 numerously distributed over the tentacula, that the reader will 

 fully appreciate the mechanism we are so inadequately describing. 

 Machines of human construction admit of being variously esti- 

 mated, as they are found to be more or less adapted to accomplish 

 the object of the contriver : but in estimating the works of the 

 DEITY all degrees of comparison are merged in the superlative ; 

 everything is best, completest, perfect. 



Examine any one of these thousand suckers, it is an admirably 

 arranged pneumatic apparatus, an air-pump. The adhesive disc 

 {Jig. 202, A) is composed of a muscular membrane, its circum- 

 ference being thick and fleshy, and in many species supported by a 

 cartilaginous circlet, so that it can be applied most accurately to 

 any foreign body. In the centre of the fleshy membrane is an 

 aperture leading into a deep cavity (6), at the bottom of which is 

 placed a prominent piston (c), that may be retracted by muscular 



