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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, w r e 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 w T hile, especially in w^arm and humid 
w T eatlier, there will soon appear a great quantity of lumbrici, 
