74 



will speedily defoliate a tree. As they attack many ornamental shade trees as well as 

 those in the forest and sometimes extend their ravages to fruit trees, they should be ruth- 

 lessly exterminated wherever they are met with. 



We have now remarked upon some of our most common insect pests, and have 

 endeavoured to furnish the reader with the most approved modes of dealing with them. 

 We shall feel very thankful to any one who tries any of these remedies if he will be 

 good enough to let us know how far they have proved successful. The experience will 

 be of much value to us and we shall probably be able to make it of service to others. 



A TRIP TO NEPIGON. 



Some Notes upon Collecting and Breeding Butterflies from the Egg. 



by james fletcher, ottawa. 



It is a recognized fact in Economic Entomology that the most important investi- 

 gations are those by which the life-histories of insects are made out, in order that the 

 most appropriate remedies may be adopted for injurious species. In Scientific Ento- 

 mology these investigations are no less important, but are undertaken with different objects 

 in view. For the accurate determination and separation of closely related species, it is 

 frequently necessary to know an insect in all its stages from the egg to the perfect form. 

 In no branch of Natural History is this more necessary than with some of our Diurnal 

 Lepidoptera — the butterflies — those living flowers which flitting from blossom to blossom 

 add such an unspeakable charm to the summer landscape. In the North American insect 

 fauna we have some very large genera, as the Fritillaries (Argynnidce) and the Clouded 

 Yellows (Coliades). These contain many closely allied species, and it would actually be 

 difficult in all cases to identify with certainty the perfect insects, without a knowledge of the 

 preparatory stages, and some have only been shown to be distinct by breeding from the egg, 

 and noting carefully the points upon which they constantly differ in their various stages 

 of growth. Whilst, in the first case, the exact scientific identification of the insect, its 

 classification, name and specific value are of little interest, so that so much of its habits 

 can be discovered as will enable us to put a stop to, or prevent a recurrence of its 

 ravages ; in the other case, the exact identification and correct classification are the 

 important points aimed at. Sometimes, as in the well-known cases of Papilio Ajax, Colias 

 Uurytheme and Grapta Interrogatlonis, several apparently very different varieties have been 

 shown to be merely varietal forms of one species, and the interesting discovery has been made 

 that one or other of these forms preponderates at certain seasons of the year. These dis- 

 coveries are chiefly due to the constant and untiring labours of Mr. W. H. Edwards, of West 

 Virginia, who not only himself patiently and persistently perseveres in his studies, but 

 has also taken great pains to induce others to help in the work. His kindness and 

 prompt attention in advising and helping others cannot be too highly spoken of. In 

 the Canadian Entomologist, for 1885, appeared some admirable articles upon breed- 

 ing from the egg, in which the results of his long experience were given. These have 

 been of great assistance to those who have taken up this most interesting branch of 

 entomology, and the writer acknowledges with gratitude his own indebtedness. Those 

 who have never caught a butterfly and caged it to obtain its eggs, and then bred these to 

 maturity, cannot form the slightest idea of the all-absorbing interest and pleasure that 

 attend these observations. Moreover, their utility, as teaching what to observe, how to 

 observe it, and then how to record what is seen, so that it may be of use to others, cannot 

 be over-estimated. At first, of course, there are some difficulties, but with a little 

 practice these can be overcome. This fact is particularly manifest in drawing or de- 

 scribing the young caterpillars at the different moults. All caterpillars change their 

 skins four or five times after they leave the egg, so as to allow for the rapid increase 

 in size of their growing bodies. At all these moults, important changes in the 

 structure and in the markings of the skin take jplace, and for this reason they 



