REARING LEPIDOPTERA 119 



we must now see what can be done to minimise the death rate of 

 the captives. 



One or more suitable boxes must be prepared for the recep- 

 tion of the pupae, and the following suggestion will answer all 

 purposes : 



Get a wooden box, quite rough and unplaned inside, large enough 

 to accommodate your pupae with ease, and not less than eight 

 inches deep. Make several holes in the bottom, or else knock the 

 bottom completely out, and nail in its place a sheet of perforated 

 zinc. Also make a lid consisting of gauze attached to a light wood 

 frame. 



Place a layer of clean gravel, about an inch deep, in the bottom, 

 and over this a few inches of sifted soil or cocoa-nut fibre. 



Now take all the pupae that are ' earthed ' in your cages, and 

 arrange them on the prepared bed; also add to them the pupae 

 you may have dug out during your various excursions. Cover all 

 with a layer of the material selected for the bed, and then add a 

 layer of moss. 



Next come the pupae that are suspended by silky fibres, or are 

 inclosed in cocoons. These should be fixed with pins around 

 the sides of the box, running the pins either through the tuft of 

 silk at the ' tail,' or the outer layer of the cocoon, or through the 

 portion of the dried food plant to which they are attached. 



Here your pupae will remain till they emerge, and the box may 

 be kept in any airy place where it is not likely to be forgotten, for 

 it is essential that the perfect insects should be removed as soon 

 as possible after quitting their cases. It does not matter_much 

 whether the pupae be kept in or out of doors, providing they are 

 sheltered from rain and very severe frosts ; but of course, if the 

 former, the imagines will emerge a little earlier, even if the room 

 in which your specimens are stored has no fire. 



Even when protected in boxes such as that described the pupae 

 are subject to enemies and dangers. The soil and moss employed 

 may contain slugs, mites, or other creatures which prey on insects, 

 and the amount of moisture present in these materials and in the 

 atmosphere may prove too little for some species or too much for 

 others. 



The remedy for the former evil is a simple one. Bake the soil 

 or fibre well before fitting up the box, and boil and afterwards dry 

 the moss. You may then be sure that all life previously contained 

 is quite destroyed. 



