Current Literature 533 



thing possible about the seasonal and life history of all insects 

 having an economic bearing, however small this role may be, as 

 the only means of discovering available opportunities for com- 

 bating them if they are injurious, or utilizing their services if 

 they are beneficial. The paper before us is another illustration 

 pointing to the emphasis to be laid on as nearly complete a knowl- 

 edge as possible of the habits of an injurious insect. The Zim- 

 merman pine moth, the author demonstrates, is most injurious to 

 second growth, on which we would apparently be utterly help- 

 less in combating it under forest conditions where the use of 

 insecticides is out of the question. But his careful, two-year 

 study of the insect showed that it inhabits dominantly also some 

 old lightning-struck or gnarly branched trees left standing in 

 the midst of old clearings. These trees serve the moth largely 

 as '"brood trees," as the author calls them, and thus to stock the 

 area with it. It becomes perfectly patent, therefore, that the 

 removal of such brood trees should practically eliminate the 

 insect as a serious pest. The actual experiment cited shows this 

 conclusion to be operative in practice, and the recommendation 

 is made accordingly. 



J. K. 



Report of the Sixth Annual Meeting of the Commission of 

 Conservation of Canada. Ottawa. 1915. Pp. 333. 



In this report, well-informed discussions are given concerning 

 Canada's resources in forests, fields, mines and streams and 

 important papers are included on technical education, agricul- 

 tural instruction, providing sanctuaries for birds ; and an impor- 

 tant place is given to housing and town-planning. 



The address of the Chairman, Sir Clifford Sifton, is an excel- 

 lent summary of the Commission's activities for the last fiscal 

 year. 



Although the war has hampered some aspects of the work of 

 the Commission, steady progress has been made in the matter of 

 town-planning. The National City Planning Conference held in 

 Toronto in 1914, and for which the Commission acted as host, 

 gave a marked impetus in Canada to this important economic 

 and social question. The Commission secured the services o£ 



