22 THE OCTOPUS. 



have, in addition to the eight corresponding limbs, two long ten- 

 tacular arms, which, in some genera, are marvellous in the perfec- 

 tion of their compound apparatus for securing and holding a 

 struggling captive. This arrangement is well suited to their habits 

 and mode of life. Animals purely swimmers, and which hunt and 

 overtake their prey by speed, would be impeded by having to drag 

 after them a bundle of lengthy appendages trailing heavily astern. 

 But a long reach of arm is an advantage, instead of a hind- 

 rance, to the octopus ; for, although it can swim on occasion, its 

 ordinary habit is, either to rest suspended to the side of a rock, 

 to which it clings with the suckers of several of its arms, in the 

 position shewn in the frontispiece, or to remain lurking in some 

 favourite cranny ; its body thrust for protection and concealment 

 well back in the interior of the recess ; its bright eyes keenly on 

 the watch ; three or four of its limbs firmly attached to the walls 

 of its hiding place — the others gently waving, gliding, and feeling 

 about in the water, as if to maintain its vigilance, and keep itself 

 always on the alert, and in readiness to pounce on any unfortunate 

 wayfarer that may pass near its den. To small fish, crustacean or 

 mollusc, the slightest contact with even one of those lithe arms is 

 fatal. Instantaneously as pull of trigger brings down a bird, or 

 touch of electric wire explodes a torpedo or a mining fuse, the 

 pistons of the series of suckers are simultaneously drawn inward, 

 the air is removed from the pneumatic holders, and a vacuum 

 created in each ; the victim strives to escape ; a further retraction 

 of the central part of the disc makes all secure ; and, as arm after 

 arm, containing a perfect mitrailleuse of inverted air-guns, takes 

 horrid hold, battery after battery of them is brought to bear, and 

 the pressure of the air is so great that nothing can effect the re- 

 laxation of their retentive power but the destruction of the air 

 pump that works them, or the closing of the throttle-valve by which 

 they are connected with it.* 



* See page 44. 



