248 THE PLANT WORLD. 



REVIEW. 



Entomology, unth special reference to its biological and economic 



aspects. By Justus Watson Folsom, instructor in entomology 

 ^at the University of Illinois. 8vo, pp. 7 -{-485. Five plates 



(one colored and 300 figures). Philadelphia: P. Blakiston's 



Son & Co., 1906. $3.00. 



This is a book which does not belong to the how-to-know class, 

 but which, nevertheless, may be suspected to be of value to the 

 learner in entomology, and will lead him, if real knowledge is 

 sought, to more than the superficial view of insects, such as some 

 may have in spite of many years of diligent " pinning." The 

 treatment is biological, and as so much has been learned about 

 insects in the last few years which has not got into the books, the 

 author has had a rich harvest to draw upon. The reviewer is 

 not an entomologist, but is enough interested to feel that the book 

 has a real value for him and infers this to be true for many others, 

 at least as far as the large body of information is concerned. The 

 treatment of the speculative aspects of the science which, of 

 course, are those which it shares with the other, particularly nat- 

 ural, sciences, is hardly as lucid as it might be, and these may well 

 have been sacrificed to a fuller and more satisfying discussion of 

 other matters. It is to be feared that the usefulness of the 

 book, good as it is, has been curtailed by the desire for complete- 

 ness. The world from the entomological point of view is too big 

 a subject for one work. A large and presumably fairly, if not 

 entirely exhaustive, bibliography covers nearly sixty pages, and 

 this will be of permanent usefulness to the student. The taxonomy 

 of the subject is left to the other well-known works. Of the type 

 of Packard's " Insects," but brought down to the present, it will 



serve in the place of this well-known work. 



L. 



