﻿THE REARING OF LARV/E. 165 



like so much space ; indeed, I have bred through from ova to 

 pupfB quite a number of the small Geometers in glass-topped 

 metal boxes throughout. Only last year I was quite successful 

 with a number of Eulype hastafa larviB bo treated, about twelve 

 to a 3J in. box. I do not suggest that that is the best sort of 

 house for larvfe so large, but simply quote it to show what can 

 be done in that direction. As already mentioned, it is most 

 difficult to generalise as to space ; the individual habits of larvffi 

 of different species make so much difference. Gregarious larvse, 

 for instance, such as Malacosoma neustria, require little space — at 

 any rate, until they separate. Also Lymaiitria monacha and 

 Dasychira i^ndihitmhi and some others stand a great deal of 

 crowding without hurt; whereas, on the other hand, soft fleshy 

 larvae, and particularly any species which tend to cannibalism, 

 require a lot of room. Larvse which are found in nature much 

 separated, such as one to a plant, should be treated liberally in 

 the matter of space ; while larvae which are found several together 

 will generally stand more crowding. In dealing with larvae 

 whose habits are unknown it is always best to give as much room 

 as can possibly be managed. 



Pupating Material. 



The choice and condition of the pupating material most 

 suitable to the species being bred is a matter of considerable 

 importance. I have known some quite experienced entomolo- 

 gists who acted on the principle that ordinary garden mould 

 was all that was required for any larvae which weut under- 

 ground for pupation, and then complained that certain species 

 were very difficult to get to pupate. Now garden mould varies 

 enormously ; mould from one garden might be nearly all clay, 

 while that from another not half a mile away would be nearly 

 all sand. Apart from that, however, some larvae require quite a 

 special type of material, while the majority do best in a light, 

 fibrous, sandy sort, more analogous to pure leaf mould, and very 

 different to the ordinary soil in any garden. Then, again, for 

 convenience in manipulation the material should have nothing 

 in it which could be mistaken for a cocoon, i. e. no lumps, stones, 

 &c. ; it should also be easily able to be moistened to any degree 

 required, and, most important of all, should be free from any 

 insect pests. Coconut fibre is an almost ideal substance in 

 certain ways, especially when it can be used without treatment; 

 but the worst of it is that it is liable to be infested with insect 

 pests, and if raised to a high temperature to kill these it becomes 

 tindery and is then apt to be very dusty when dry, and sloppy 

 and unpleasant when moistened. Well-matured, soft, brown 

 peat rubbed up fine, passed through a sieve, and mixed with a 

 little fine silver sand, makes a compost that will suit quite nine- 



