426 PRESERVATION OF INSECTS. 



wooden or wire frames ; each compartment has a separate 

 door, and is, moreover, furnished with a phial in the centre, 

 for the purpose of containing water, in which the food is 

 kept fresh ; and is half-filled with a mixture of fine earth 

 and the dust from the inside of rotten trees, the latter 

 article being added for the purpose of rendering the former 

 less binding upon the pupce,* as well as highly important 

 for the use of such larvoe as construct their cocoons of rotten 

 wood. The chief advantages of a breeding-cage of the 

 above description are the occupation of less room than five 

 separate cages, and a diminution of expense ; both important 

 considerations when any person is engaged extensivel}' in 

 rearing insects. Whatever be the construction of the box, 

 it is highly necessary that the larvse be constantly supplied 

 with fresh food, and that the earth at the bottom should be 

 kept damp. To accomplish the latter object, I keep a 

 thick layer of moss upon the surface, which I take out oc- 

 casionally, perhaps once a week in hot weather, and once 

 a fortnight or three weeks in winter, and saturate com- 

 pletely with water, and return it to its place : this keeps 

 up a sufficient supply of moisture, without allowing the 

 earth to become too wet, which is equally injurious to the 

 pupae with too much aridity. By numbering the cells, and 

 keeping a register corresponding with the numbers, the 

 history of any particular larvae or brood may be traced. "f 



AVe prefer glass sides to the cells, with gauze doors, 

 opening above, rather than at the sides, according to the 

 following figure. (J. E.) 



Some of the beautiful experiments of Bonnet and Eeaumur 

 suggested to us the idea of supplying insects with growing 

 food, instead either of gathered leaves or branches kept 

 fresh in water ; and we have in several instances, particu- 

 larly in town, where we could not always procure fresh 

 food for our broods when wanted, kept plants growing in 

 garden-pots, and either confined the insects by means of 

 gauze, or surrounded the pots with water, to prevent their 



* The French naturalists use fine dry sand. See ' Manuel du Xatur- 

 aliste Preparateur.' 



t Ingpen's 'Instructions,' p. 13. 



