2l8 ENTOMOLOGICAL NEWS. [May, '09 



American Agriculturist ; The National Nurserymen ; THE 

 ENTOMOLGICAL NEWS and the Canadian Entomologist. He 

 was a contributor to the Encyclopedia of American Agricul- 

 ture. At the time of his death he had in preparation a vol- 

 ume entitled " Insects Injurious to Fruit," which was to ap- 

 pear in Macmillan's Rural Science Series. 



The position he attained was reached by untiring industry 

 and a devotion to truth ; his work was characterized by pains- 

 taking thoroughness and an absence of anything sensational. 

 His constant aim was to determine the exact and complete 

 truth and to present what he discovered in a clear manner. In 

 this he was very successful, both in the class room and as a 

 writer. 



The bulletins that he published were in a marked degree 

 monographic. Instead of writing about many insects, he se- 

 lected a few and diccussed them thoroughly, working up so 

 far as possible every detail in the life-history of the species 

 studied. It was doubtless this feature that caused his work to 

 be so widely known in other lands. For example, his treatise 

 on the Codling Moth was translated into Russian and pub- 

 lished in that language. 



A striking feature of Professor Slingerland's bulletins is the 

 excellence of the illustrations ; no one else has been so success- 

 ful as he in photographing entomological subjects ; and his 

 lantern slides of insects, colored by Mrs. Slingerland, are un- 

 surpassed. 



Although his work is characterized by the highest degree of 

 scientific accuracy, he never forgot that the object of his work 

 was to aid those that till the soil. He never allowed his inter- 

 est in the purely scientific aspects of the subjects studied to 

 cause him to neglect the practical applications of the results 

 obtained. A marked instance of this was his invention of the 

 "Spray Calendar; ' for he devieed the first tabular calendar 

 arrangement of spraying suggestions. This was printed and 

 used at Farmers' Institutes in 1894. The value of this method 

 of publication was apparent at once ; and it has been generally 

 adopted by experiment stations. 



Professor Slingerland took an active part in various scien- 



