36 THE CANADIAN ENTOMOLOGIST 



comparatively simple means of identification is thus being put into 

 the hands of working entomologists. 



In this monograph one hundred and forty-five species and 

 varieties belonging to sixteen genera are described. Excellent 

 figures are given of the genitalia in one hundred and thirty-eight 

 cases. The species can be readily divided into eight groups by 

 not restricting the separation to generic characters but by using . 

 the most salient and easily recognizable characters that can be 

 found. In a large number of cases the female has not been de- 

 scribed, and the author rightly admits the possibility of errors 

 occurring through the identification of females with the wrong 

 males, as few pairs collected in copula exist in the collections he 

 has examined, which collections, by the way, include the chief 

 collections of Sarcophagidse on this continent. 



Ninety-five new species are described and several new varieties. 

 Five of these new species and one new^ variety occur in Canada. 



When we remember that in the author's Catalogue of North 

 American Diptera, one hundred and six nominal species of Sar- 

 cophaga were listed and that hardly more than half a dozen of 

 these had been described in a manner that would permit recogni- 

 tion, the extent of our indebtedness to him for this contribution 

 will be readily appreciated. He has placed both systematists and 

 economic workers under a debt of gratitude for his painstaking 

 work which will undoubtedly stimulate others to study this group 

 of fiies, the investigation of whose habits is rapidly disclosing the 

 economic importance of the group. 



We cannot conclude this review without remarking on the 

 excellent manner in which the monograph is printed and bound, 

 and we hope that this standard will be maintained in future volumes 

 of this series. It is unfortunate that in the author's desire to make 

 the work immediately available, a number of typographical errors 

 have been overlooked, and we think that the inclusion of an out- 

 line sketch of Sarcophaga would have added to the value of the 

 introductory description. 



C. GORDON HEWITT, 



Mailed January 24th, 1917. 



