326 WORMS AND ZOOPHYTES. 



tbofe of ferpents. There is a fpiral mufcle that runs round the body, 

 from head to tail, fonnewhat refembling a wire-fpring to a bell which is 

 • hung from room to room ; which, if one end be extended and held faft, 

 will bring the other nearer to it : by this the earth-worm, havino- ex- 

 tended itfelf, holds by the flime of the fore part of its body, then con- 

 tra£t,s itfelf and brings forward the hinder part. 



Its body is armed with fmall ftifFfliarp burs or prickles, which it can 

 cre6l or deprefs at pleafure ; under the fkin lies a flimy juice, ejeded as 

 required, at certain perforations, between the rings of the mufcles, to lu- 

 bricate its body, and facilitate its paflTage into the earth. It has breath- 

 ing-holes along the back, adjoining each ring. Dellitute of head, ears, nofe, 

 .for the moft part of eyes, and properly without feet. It has a mouth, 

 and an alimentary canal, which runs to the very point of the tail (but in 

 fome found in the bodies of animals, this canal opens towards the middle 

 of the belly), filled with a very fine earth, which feems to be their nou- 

 rifhment. 



Without brain, but near the head is the heart, which beats diflinflly ; 

 round it are thefpermaticvefTels, forming a number of little globules, con- 

 taining a milky fluid, opening into the belly, not far from the head : they 

 are alfo often found to contain eggs, which are laid in the earth, and. 

 hatched in twelve or fourteen days, by the warmth ^ like fnails, thefe ani- 

 mals unite in themfelves both fexes. 



The young ones are very fmall, but perfeflly formed, and fufFer no 

 change : how long they live is not known, certainly more than two or 

 three feafons. During winter, they bury themfelves deep, and feem to 

 (hare the general torpidity. In fpring they revive, a moifl or ^ewy even- 

 ing brings them from their retreats, for mutual intercourfe. They chief- 

 ly live in a light, rich, and fertile foil, moiftened by dews or accidental 

 fhowers, but fhun where the water is apt to lie, or the clay is too ftifF. 

 They avoid the mole, who feeds on them, by darting up from the earth, 

 the inflant they feel the ground move ; and fifhermen take them in num- 

 bers, by ftirring the earth. 



The Earth Worm continues to live, though cut in feparate parts. 

 We owe the difcovery of this power of reprodudion in animals to Mr. 

 Trembley, who firft obferved it in the polypus; after him, Spalanzani 

 and others found it in the earth-worm, the lea- worm, and fevcral other 

 animals. Every earth-worm, however, did not retain the vivacious 

 principle equally; fome, when cut in two, were deftroyedj of others, while 

 the head was living, the tail perifhed, and a new tail came at the extre- 



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