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extent of which we do not know, they deposit their young in 

 the earth. We are no better acquainted with the time which 

 they take to acquire the necessary development for repro- 

 duction, and for attaining their largest size. Neither do we 

 know any thing concerning the duration of their life. 



The lumbrici are in full possession of their faculties only 

 during the seasons of spring, summer, and a part of the 

 autumn. In proportion as the cold approaches, they sink 

 deeper and deeper into the earth, where, according to M. 

 Latreille, they form a sort of lodgment, or case, probably 

 with the mucous matter which issues from their bodies. 

 Under certain circumstances, the nature of which does not 

 appear to be sufficiently understood, the lumbrici become 

 phosphorescent. Experiments have been tried upon them, 

 respecting their capacity of reproducing parts removed. 

 Some authors tell us that they have even seen the parts of a 

 lumbricus cut in two, become each of them a complete 

 animal. 



This is conceivable respecting the anterior half, because it 

 contains almost all the essential parts of the organization, 

 and that, so to speak, there is nothing to form but an anus ; 

 but it is not probable that the posterior moiety can repair the 

 loss of the stomach, the organs of generation, &c. The 

 lumbrici are scarcely of any other use to the human species 

 than as bait for fish. They are procured by searching for 

 them, with spade or fork, in the unctuous or loose soils of 

 our kitchen-gardens, &c. or even by stamping on and dis- 

 turbing the soil in which, from the multitude of holes by 

 which it is pierced, we may recognize that there is an abun- 

 dance of these animals. What comes to the same thing, is 

 by sinking the spade or a stake in the earth, to cause all " 

 around a considerable commotion and pressure. If this ope- 

 ration be continued for a while, especially in waim and humid 

 weather, there will soon appear a great quantity of lumbrici, 



