ntoitmloj^bt. 



Vol. XXXVII. 



LONDON, MAY, 1905. 



No. 



PRACTICAL AND POPULAR ENTOMOLOGY.- No 5. 



Canadian Three Colour Process Illustrations. 



by james fletcher, ottawa. 



We are indebted to the Toronto Engraving Company, Limited, for 

 the beautiful plate given in this month's issue. The invention of the 

 trichromatic photographic process of ilkistration is undoubtedly one of 

 ■the most important stimuli to scientific work of recent years. Especially 

 is this the case in the study of insects, where it is frequently necessary to 

 depict accurately very slight difterences, both in form and colour, which 

 could be described only with difficulty, or at great length. The three- 

 colour process makes it now possible to reproduce, with great exactness, 

 any coloured object that may be desired, and at a moderate cost. As 

 excellent examples of this kind of work in illustrating insects, we may 

 refer to the many beautiful figures which have appeared in the pages of 

 our esteemed contemporary " Entomological News," as well as those 

 which have also adorned some of cur own issues. 



Up to the present time the best class of this work has all been done 

 in the United States, but we are now able to present a plate done entirely 

 in Canada by the Toronto Engraving Company, Limited, wliich, to the 

 writer, seems to be equal to the best imported work. Anyone wishing to 

 get full partioulars as to cost, etc., should correspond directly with the 

 above firm. 



The insects figured on the accompanying plate were chosen with the 

 special purpose of showing a wide range of colouring. The species are 

 so well reproduced that there will be no trouble in recognizing all of them. 



Figures i and la represent the Large Ermine. Estigmetie acrcea, 

 Drury, female and male. This beautiful moth, which is common in all 

 parts of Canada, is the perfect state of the so-called Salt-marsh Caterpillar, 

 a name which was given to it many years ago by Dr. Harris, and of which 

 an interesting account is given in his classic work on the Insects Injurious 

 to Vegetation. The full-grown caterpillar is one of the common " woolly 

 bears " and when full-grown is over an inch and a half in length. It is 



