.REARING LEPIDOPTERA 



115 



the stem and the rim with cotton wool. This precaution is to 

 prevent the larvae from falling into the water as they attempt to 

 pass up or down the stem, and the wool also helps to keep the 

 twig in a vertical position. The glass is now ready for the cater- 

 pillars, but it is advisable to keep a covering of muslin or gauze 

 over the top in all cases even though the larvae contained are unable 

 to creep up the surface of glass, for the great enemies of caterpillars 

 the ichneumon flies are always on the alert, and will often take 

 advantage of an open window to 'sting ' the larva rearer's pets. 



Another form of larva glass can easily be made out of a large 

 glass jar if you know how to cut off the bottom, or of a chemist's bell 

 jar which is open both at top and bottom. In this case the bottle 

 of water and the soil are arranged as 

 before in a pan of unglazed earthen- 

 ware, and then covered over with the 

 glass. This is shown in fig. 58, and is 

 an exceedingly convenient larva house, 

 since the lifting of the glass enables 

 you to get at the insects without any 

 trouble. 



Wood larva cages are ver} r com- 

 monly used for the larger species after 

 they have attained a fair size and re- 

 quire more food than can be stocked 

 in bottles and glasses. These cages 

 have glass fronts, either sliding or in 

 the form of a hinged door, and sides 

 of perforated zinc. They are kept in 



stock by all dealers in entomologists' requisites, but equally useful 

 ones are easily constructed. If you select a box of suitable size at 

 the grocer's, cut out large pieces from the lid and sides with a fret 

 saw, and fix in the glass and zinc, you will have a cage that will 

 answer all purposes. 



The internal arrangements consist of a shallow tray filled with 

 soil, in which stands the bottle of water for the food, and a layer of 

 moss sufficiently high to cover the bottle completely. 



A series of such boxes standing on end on a shelf, or hanging on 

 a wall, will form a very satisfactory nursery for your pets, and will 

 occupy but little space. 



We have already observed that some larvae burrow into soil 

 when about to change, while others creep to a sheltered corner, or 



i2 



FIG. 59. -A. LARVA CAGE. 



