86 ETON NATURE-STUDY 



are kept, it will be necessary to feed them by putting honey on the 

 flowers. The " Camberwell Beauty" is another form which may be 

 successfully reared in confinement. Tn many cases it will be 

 necessary to get a stock from a collector or dealer. There are, how- 

 ever, plenty of insects of similar or other kinds which may be 

 obtained by the student himself. 



In almost any pond or stream the larvae of the dragon-fly may 

 be found. Even in a London back garden the interesting life 

 history of the hover-fly may be completely watched. This insect 

 looks like a small wasp, but has only two wings, and lays its 

 eggs among the aphides which attack the more juicy plants of 

 the garden. A little patience will enable the observer to see the 

 actual deposition of the egg (see figure 201), which under a lens is 

 rather a pretty object. The young grub in the course of a few days 

 hatches out and begins to feed upon the aphides (see figure 202), de- 

 stroying a prodigious number of these before it turns into a pupa 

 and completes its life history (see figure 200). 



It should be mentioned that a bag of muslin known as a " sleeve," 

 which is placed over the part of a plant or the branch of a tree, 

 obviates the necessity for " breeding cages " for many insects. The 

 caterpillars or larvae can be placed in the sleeves and the open end 

 tied securely round the branch. The leaves keep quite fresh until 

 they are all eaten up, when the insects can be transferred with their 

 covering to a new branch. In the same way the grubs of hover- 

 flies, or other insects which feed on aphides, may be kept under 

 observation. 



The more advanced student may well turn his attention to the 

 subject of cross-breeding butterflies and moths, upon which com- 

 paratively very little work has been done. 



