CEPHALOPODA. 67 



nel, and crawls in a reversed position, carrying its shell over its back like a 

 snail. [Madame Power and 31. Rang.) 



It was the nautilus {primus) of Aristotle, who described it as floating on 

 the surface of the sea, in fine weather, and holding out its sail-shaped arms to 

 the breeze ; a pretty fable, which poets have repeated ever since. 



Distribution : 4 species of argonaut are known ; they inhabit the open sea 

 throughout the warmer parts of the world. Captain King took several from 

 the stomach of a dolphin, caught upwards of 600 leagues from any land. 



Fossil : A. hians is found in the sub-apennine tertiaries of Piedmont. This 

 species is still living in the Chinese seas, bvit not in the IMediterranean. 



FAMILY IT. OCTOPODID^. 

 Arms similar, elongated, united at the base by a web. Shell represented 

 by two short styles, encysted in the substance of the mantle, (Owen.) 



Octopus, Cuvier. Poulpe. 



Etym., octo, eight, /JC>^w {poda) feet. 



Si/n., cistopus. {Gray.) 



Ex., 0. tuberculatus Bl., pi. I., figs. 1 and 2 (mandibles). 



Body oval, warty or cirrose, without fins ; arms long, unequal ; suckers 

 in two rows ; mantle supported in front by the branchial septum. 



The octopods are the "polypi" of Homer and Aristotle; they are solitary 

 animals, fi-equenting rocky shores, and are very active and voracious ; the 

 females oviposit on sea-weeds, or in the cavities of empty shells. In the 

 markets of Smyrna and Naples, and the bazaars of India, they are regularly 

 exposed for sale. "Although common (at St. Jago) in the pools of water left 

 by the retiring tide, they are not very easily caught. By means of their long 

 arms and suckers they can drag their bodies into very narrow crevices, and 

 when thus fijsed it requires great force to remove them. At other times they 

 dart tail fii-st, with the rapidity of an arrow, from one side of the pool to the 

 other, at the same instant discolouring the water with a dark chesnut-brown 

 mk. They also escape detection by varying their tints, according to the nature 

 of the ground over which they pass. In the dai'k they ai"e slightly phospho- 

 rescent." {Darwin.)'' 



Professor E. Forbes has observed that the octopus, when resting, coils its 

 dorsal arms over its back, and seems to shadow forth the argonaut's shell. 



Distr., universally found on the coasts of the temperate and tropical zones ; 

 46 species are known ; when adult they vaiy in length from 1 inch to 2 feet, 

 according to the species. 



PiNNOCTOPus, D'Orb, Finned octopus. 

 Body vdth. lateral fins, united behind. 



* Journal of a Voyage round the World. The most fascinating volume of travels 

 pubhshed since Defoe's fiction. 



