PROCEEDINGS. IDIG 27 



point aljout takini^- out the pupae is that they are then much easier to 

 handle and look after and to place, so that they get the full benefit of 

 the damp atmosphere which is so necessary to most species just before 

 emero-ence. When, in addition to this, it is realized that the removal 

 of the pupae, if carefully done, does them no harm, and adds to the 

 percentage of emergences, there seems no tangible reason for leaving 

 pupae in situ. 



"I do not I)}' all this mean that every cocoon should be opened and 

 the pupae removed. As long as the cocoons are fairly substantial there 

 is no object to be gained by doing more than separating the cocoons one 

 from the other, and removing the loose outer web if there is one. Indeed, 

 from the difficulty of doing so without injury, it is unwise to attempt to 

 remo\'e pupae from tough cocoons." 



"When dealing with larvae whose period of rest is tmknown. the 

 receptacle in which they have gone down should be left untouched for a 

 fortnight, then the compost in one corner should be gently removed till 

 one of the insects is found ; if it is a thoroughly hard pupa, the lot ma}- 

 be turned out with safety; if, on the other hand it is still a larva, leave it, 

 slightly exposed if possible, so that it can be inspected every few days. 

 In this way the period of rest can be found out, and, at any rate, th'e 

 breeder does not endanger the whole brood. The chief thing in keeping 

 bare pupae over any length of time is to prevent them coming into 

 contact with anything that will block up their spiracles. The)' should 

 never be allowed to lie on, or in any dusty material, such as dry earth. 

 Bare pupae and cocoons can quite easily be kept during the winter 

 piled into and shut up in chip or glass-topped boxes exposed to outdoor 

 temperature." 



"About a month or more before the time arrives for the emergence 

 of the perfect insect, the pupae and cocoons should be spread out in 

 shallow pans or boxes, the bare pupae between two la;^ers of sterilized 

 moss, and placed in a cage or large, well ventilated box with rough 

 sides and top. The atmosphere in this box should be kept decidedlj' 

 damp, or many cripples will be bred, especially amongst the Geometers. 

 The pupae of many species do not all emerge the first year, a provision 

 of Nature that has no doubt saved many an insect from extinction ; but 

 this class of pupae does not seem to call for any special treatment, unless 

 it be extra care in making sure a pupa is really dead before throwing it 

 away." 



That is all I have to say about larvae-rearing toda}'. I am con- 

 scious that all the members present may not feel greatly interested in 

 the subject, and may think that I might have chosen a less common- 

 place one, but my excuse must be that I wish to encourage the practice 

 of larva-rearing; for it is a sad fact that in the case of a great number 

 of our insects, little or nothing is known of their earlier stages. 



