PROCEEDINGS OF THE THIRD ENTOMOLOGICAL MEETING 877 



made of muslin or mosquito-netting whose open end is tied around the 

 stem of the. plant (or whose ends are tied around a branch on either side 

 of the place where the insects are feeding) so that the insect under reariu" 

 is allowed to feed under fairly natural conditions but cannot escape out- 

 side of the " sleeve." " Sleeving," however, is not very satisfactory 

 in a coimtry such as India, as such " sleeves " quickly rot and are very 

 liable to tear or may be torn open by birds or other animals or even 

 removed altogether by human bipeds. 



Generally, therefore, it is necessary to rear insects such as caterpillars 

 on cut portions of their foodplants placed withia closed receptacles and 

 in such cases the effect of a hot climate at once makes itself felt. Cut 

 portions of plants, which in a cool climate would remain tolerably fresh 

 for a day or more, wilt almost immediately in the hot weather whilst 

 during the monsoon the plant-food and excrement of the insects under 

 rearing form very favourable media for the rapid growth of moulds. 

 Especial care therefore is required to keep the breeding cages (of what- 

 ever construction) quite clean by removing all excreta and uneaten leaves 

 at least once a day, if not oftener. Otherwise, mould will quickly appear 

 on these and the insects are likely to be affected. 



For casual rearing on a small scale a small meat-safe makes a con- 

 venient cage, the necessary foodplant being kept fi-esh by having its 

 stalk inserted in a jar of water. Or a collapsible meat-safe (of the type 

 made of mosquito-netting stretched over bamboo rings) may be placed 

 over the jar or bottle containing the foodplant and tied securely around 

 the neck of the jar, the upper end being suspended by a string from any 

 convenient support. If the stalk of the foodplant does not fill the neck 

 of the jar, the latter should be packed with a thick wad of cotton-wool, 

 otherwise caterpillars are very hable to crawl down and drown themselves 

 in the water. (PI. 131, fig. 1.) 



For more regular rearing of insects, however, it is necessary to provide 

 proper apparatus, wliich comprises : — 



Glass jars and troughs. 



Zinc cages. 



Zinc cylinders. 



Muslin cages. 

 Glass jars. At Pusa we use glass dishes and glass battery jars (as 

 illustrated in PL 132) in different si^es, from small to large. For 

 covers of these cages we use either glass plates with one side ground or 

 brass plates (PI. 132). In dry weather leaves kept in cages retain mois- 

 ture for several days and remain fit to serve as food to the insects to which 

 they are supplied. In moist weather in the rains, however, whole covers 



