ENTOMOLOGY. 245 



from jumping and skipping like a flea, scarcely ever 

 moves or walks. 



The polypus can contract or extend its body at 

 pleasure, from the length of an inch or more, and the 

 thickness of a hog's bristle, to the shortness of a sin- 

 gle line, with a proportional increase of thickness. 



Reproduction. 



Spallanzani carried the proofs of this power to 

 their utmost limits, when he caused the head, with 

 the tongue, jaws, and eyes, to be reproduced in a 

 slug, and the feet, with all their bones, muscles, 

 nerves, and vessels, in the salamander. 



This property, experimented upon in worms, pre- 

 sented Bonnet with several phenomena calculated to 

 excite astonishment: The anterior extremity, on 

 being split, afforded two heads, which, yet scarcely 

 formed, became enemies to each other. When the 

 animal was cut into three distinct pieces, the middle 

 piece commonly produced a head before and a tail 

 behind. But a sort of mistake of nature sometimes 

 occurred ; the middle piece producing two tails, and 

 being unable to nourish itself, soon ceased to exist. 



Coral Worms. 



Coral worms are of a great variety of shapes and 

 sizes. The most common is the form of a star, with 

 arms from four to six inches long ; others are so 

 sluggish as to be mistaken for a piece of the rock, 

 and are generally of a dark colour, from four to five 

 inches long, and two or three round. When the 

 coral is broken about high water mark, it is a hard 

 solid stone ; but if any part of it is detached at a 

 spot which the tide reaches every day, it is found to 

 be full of worms, of different colours and lengths ; 

 some as fine as a thread, and several feet long; 



