THE MOLLUSCA 217 



The body of such a specimen is of about the size and 

 shape of a cocoa-nut, the head, which is only marked 

 off from the body by a slight constriction, adding about 

 another three inches to the length of this. The eight arms 

 or tentacles are about three and a half feet long, about 

 three inches in diameter at the base, and tapering gradually 



Fig. 93. Octo2>us vulyaris. ^ Natural size 



down to the diameter of a straw. Two rows of suckers, 

 ranging from an inch and a half in diameter at the base 

 of the tentacles to about one-sixteenth of an inch at their 

 tip, are set so as to just touch one another throughout the 

 length of the tentacles. There are about three hundred 

 suckers to each. The tentacles are joined for about one- 

 fourth of their length by an elastic membrane, a kind of 

 " web-footed " arrangement. In the centre of the disc 



