348 THE CANADIAN ENTOMOLOGIST. 



the early part of her career ; but on this occasion, her life-work finished, 

 there is no awakening." 



'The interesting and important discoveries which the author made as 

 to the parasitic nature of the Psithyrus form a valuable portion of the first 

 part of the work. We are told how the Psithyrus queen, protected by her 

 coat of mail, impervious to the attacks of ihe Bombus queen, enters the 

 home of the latter, and, after treacherously killing her, makes slaves of the 

 workers, as she herself neither produces workers nor is provided with the 

 pollen-collecting baskets in her hind legs. 



The second part of the book describes the author's experiments in 

 domesticating the Bombi, in which many types of domiciles were used. 

 This section will prove of great value to future workers on the same lines. 

 We should point out, in passing, that there is undoubtedly an important 

 field of investigation in the encouragement of the Bombi. The economic 

 significance of the presence of these insects where clovers are grown is 

 now more generally appreciated, but we are not aware of any efforts hav- 

 ing been made for the encouragement of these fertilizing agents. It is 

 proposed to carry out in Canada investigations of the nature indicated. 



In the third section of the book all the British species of Bombus 

 and Psithyrus are described. Not only is a clear description of the queen, 

 worker and male of each species given, and a brief description of their 

 habits as observed by the author, but coloured illustrations render the 

 identification of the species possible to anyone. The coloured figures, and 

 there are five plates of them, are photographed direct from the 

 specimens, and are undoubtedly the finest specimens of this 

 kind of work which we have seen. The work is further enriched 

 by the author's own drawings and photographs. The author has demon- 

 strated, we believe for the first time, the importance of the structure of the 

 male genitalia in separating the species and groups of species. The great 

 variations in colour render such a method of separation of greater impor- 

 tance and significance. Illustrations are given of the male genitalia of the 

 British species. 



Although the author has confined himself to specific descriptions of 

 the British forms, the book is none the less valuable to entomologists on 

 this side of the Atlantic. From a monographic standpoint alone it is a 

 work which should find a place on the bookshelf of every entomologist 

 whose desires are not confined to the killing bottle and cabinet, but sit, 

 like the fairies, astride the velvet-backed bumble bee and sail along the 

 hpfigerow, over field and forest and into every nook where insect creeps. 



G. Gordon Hewitt. 

 Mailed November 8th, 1812. 



