148 THE CANADIAN ENTOMOLOGIST. 



collapsing with a shower of rain, and we think that by modifications of this 

 method success in obtaining eggs from almost all^our moths as well as butter- 

 flies might be secured. 



"We had often tried to obtain eggs from our commonest red butterfly, 

 Danais archijjpus, by confining them in boxes within doors, but never suc- 

 ceeded in this way ; but about the last of June, 1870, we captured four 

 females and shut them up in a bag as described, tied on a plant of the com- 

 mon milkweed Asclepias cornuti, enclosing a few leaves only. As early as 

 the next morning they had deposited a considerable number of eggs, which 

 operation was continued for about another day when we counted them and 

 found 150 in all, laid singly on all parts of both sides of the leaves, and also 

 on the leaf stalks and on the muslin bag in which they were confined. 



The eggs were l-25th of an inch long, and a little less in width — exact 

 measurement, 34-100ths of an inch. They were conical, quite flat at the base 

 where attached to the leaf, with about 25 raised striae or lines, and about the 

 same number of cross lines between each stria, and in the meshes of the net 

 work thus formed were slight cavities. Their color was white, with a faint 

 yellowish tinge, and they were very firmly attached to the leaves. 



Quite a number of the eggs hatched on the 5th of July, but having lost 

 the date on which the butterflies were enclosed, the exact duration of the egg 

 state cannot just now be given, but we believe it did not exceed six or seven 

 days. The newly hatched larvae were l-10th of an inch long, with a large 

 black head on which were a few dark brown hairs. The body was dull white 

 with a slight bluish tint, spaces between the segments dull yellowish, there 

 were a few black hairs on each segment, and the underside was similar in 

 color to the upper but with fewer hairs, feet black ; prolegs tipped with black. 

 We had fully intended tracing the history of this larva out, noting the number 

 of its moultings and the changes in appearance each time, but want of leisure 

 prevented us. 



The Pear Tree Slug. 



This disgusting little larva, the progeny of a little blackish sawfly, has 

 been very abundant during the past season and has been the subject of some 

 notes and experiments. In the first place we noted that there were two 

 broods in the season. The parents of the first brood, which pass the winter 

 in the chrysalis state, appear on the wing about the second or third week in 

 May, depositing eggs from which the slugs are hatched, becoming full grown 

 from the middle to the end of June, then entering the chrysalis state under- 

 ground ; the second brood of the flies make their appearance late in July. 

 This year we noticed them at work depositing eggs on the 21st, the young 

 slugs were abundant and about a quarter of an inch long on the 8th of August, 



