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the stems of the plants should be put to keep them 

 alive. It is necessary to observe, that the con- 

 stant supply of fresh plants is essential to the 

 obtaining fine specimens of the perfect insect ; 

 it is also requisite to keep the cages clean by 

 clearing away the dung, which is injurious to the 

 health of the caterpillars. When caterpillars 

 are large, which is the case with many of the 

 exotic species, it is scarcely necessary to say 

 that the cages must be in proportion. When 

 drawings can be made of the larvae, they should 

 be kept by themselves, in order to ascertain the 

 species. As most of the caterpillars in a state 

 of nature feed during the night, and secrete 

 themselves in shady and cool places in the day 

 time, the cages should be kept either in an out- 

 house or cellar; at the bottom of the % cages 

 there should always be a quantity of earth, of 

 the depth of four or five inches, for such larvae 

 as pass the pupae state underground ; and this 

 should be kept moist. As many of those insects 

 that undergo their metamorphosis below the 

 surface of the earth form an artificial cell, in 

 which the pupee can freely turn, it is hardly ne- 

 cessary to say that such must never be disturb- 

 ed: many will remain in this state for several 

 months, and some from one to two years. 



