454 PIINX'S NATTJEAL HISTOET. [Book ES. 



itching, smarting pain," just like that caused by the nettle found 

 on land. Por the purpose of seeking its prey, it contracts and 

 stiffens itself to the utmost possible extent, and then, as a 

 small fish swims past, it will suddenly spread out its branches, 

 and BO seize and devour '° it. At another time it will assume 

 the appearance of being quite withered away, and let itself be 

 tossed*' to and fro by the waves like a piece of sea-weed, until 

 it happens to touch a fish. The moment it does so, the fish 

 goes to rub itself against a rock, to get rid of the itching ; im- 

 mediately upon which, the nettle pounces upon it. By night 

 also it is on the look-out for scallops and sea-urchins. When 

 it perceives a hand approaching it, it instantly changes its 

 colour, and contracts itself; when touched it produces a 

 burning sensation, and if ever so short a time is afforded, 

 makes its escape. Its mouth is situate, it is said, at the root or 

 lower part,*" and the excrements" are discharged by a small 

 canal situated above. 



CHAP. 69. SPONGES ; THE VAEIOITS KTKDS OF THEM, AND WHEKE 



THEY ABE PHODTJCED : PEOOES THAT THEX AEE GIFTED WITH 

 LIFE BT NATURE. 



We find three*^ kinds of sponges mentioned ; the first are 



'^ Many species of the medusse, CuTier says, and other animals of the 

 same class, the pbysalus more especially, caiise an itcbin? sensation in the 

 skin when they are touched. This is noticed also by iElian, Hist. Anim. 

 B. vii. c. 36 ; and by Diphilus pf Siphnos, in Athenseus, B. iii. 



'* This is true, Cuvier says, and more especially mtb reference to the 

 actiniae. They have the mouth provided with numerous fleshy tentacles, 

 by means of wbicb they can seize very small animals which come within 

 their reach, which they instantly swallow. 



'' Cuvier says, that this is the case more especially with the medusae 

 and the physali. 



*" " Ora ei in radice." Aristotle, however, says, Hist. Anim. B. iv. c. 5, 

 and B. viii. c. 3, that the sea-nettle has the mouti situate ev likaifi, " in the 

 middle of the body." Hardouin attempts to explain the passage on the 

 ground that Pliny has made a mistake, in an endeavour to suit his similitude 

 of a tree to the language of Aristotle. Cuvier says, that there exists one 

 genua or species of the medusae, which appears to feed itself by the aid of 

 an apparatus of branches, and is divided into such a multitude of filaments, 

 almost innumerable, that it bears a strong resemblance to the roots of a 

 tree or vegetable. It is this kind, he says, that he has called by the name 

 of " Ehizostomos." 



*' Aristotle, Hist. Anim. B. viii. c. 3, says the same ; though, on the 

 other hand, in the Fourth Book, he says that the animal has no excrements, 

 although it has a mouth, and feeds. 



*' Cuvier remarks, that there are a great many more than three kinds 



