﻿THE REARING OF LARV/T:. 167 



sea-sand, and when I got home (near the centre of England) I 

 gave the larvffi about 8 in. of sand in an old lard bucket, and 

 when they were finishing feeding placed it where it would not 

 be moved or shaken. The next summer I bred quite a nice 

 little lot of rip(^, and further found that some of the pupte were 

 not more than two or three inches below the surface. Of course 

 my success in this instance may have been due to some other 

 cause, and, not living near the sea, I have not had much oppor- 

 tunity of experimenting frequently with seashore larvae; but 

 judging from experiences with other larvae of similar habits, 

 I think the success was largely attributable to the absence of 

 shaking. 



While speaking of receptacles for pupating, it may be men- 

 tioned that, though metal may be used, those constructed of 

 rough wood are infinitely preferable, except for wood-eating 

 larvcG and one or two species who seem to like stone or earthen- 

 ware to pupate on. The size and depth of the receptacles are 

 again dependent largely on the species to be treated. About 

 three or four inches deep are sufficient for the majority of bury- 

 ing larvfe, but for some of the large hawks and certain fastidious 

 things such as Apocheima hispidaria, the compost should be much 

 deeper. I lost a nice lot of the last-named once through giving 

 them too shallow a pan and allowing too many to pupate in it. 

 I believe only about ten to fifteen per cent, of the larvfe suc- 

 ceeded in turning properly into pupae. As to size of receptacle, 

 it is far better to have a number fairly small, and let only a few 

 larvai go down in each than one large one, and expect a lot of 

 larviB to go down in it. One reason is that generally the 

 majority of a batch of larvae unaccountably prefer one end or 

 corner of a pupating box ; consequently, if a large number are 

 allowed to pupate in the same box, however large it may be, 

 those which descend last will disturb those already down, with 

 bad results as to the number of pupae obtained. 



For larvae which spin up on the surface of the ground there 

 is nothing to equal natural moss (sterilized) pressed down gently 

 on to the surface of a layer of the peaty compost already de- 

 scribed. For those which spin up in dead leaves it is obvious 

 what should be supplied, while larvae which spin above ground 

 usually do not require anything special, but will make their 

 cocoons on the food-plant or cage. With such species as 

 Arctia caja, however, it is advisable to give a handful or two of 

 wood-wool, so that the majority may spin up in that "instead of 

 making a general mess of the top and sides of the cage. The 

 Dicntnura require the bark of the trees they feed on to make the 

 best job of their cocoons, but ornamental cork is not a bad sub- 

 stitute, while the wood feeders, one or two species of A crony eta, 

 and a few others demand special treatment, such as hollow 

 sticks, rotten wood, and the like. 



