REVIEWS 353 



The main feature of the book, however, lies in the descriptions of the birds* 

 Here for the first time we find complete accounts of British Birds in all their 

 various plumages from nestling to adult— an enormous undertaking. There are, 

 unfortunately, several gaps due to lack of material. The brief descriptions of 

 closely-related sub-species not on the British list are provided for the benefit 

 of travellers to the Continent. 



The colour-plates are accurate and well printed and the text figures are good. 

 It seems a pity that a plate such as Plate 3, representing five species of Redpoll, 

 should be printed in black and white, in which form it is almost valueless ; 

 while Plate 4, depicting young and adult Crossbills — often before figured — should 

 be honoured with colours. This plate is, moreover, done in the coloured-drawing 

 style, reminiscent of old-fashioned German natural history illustrations, and in no 

 way improves the present volume. 



The book is written in shorthand pithy sentences for the economising of space. 

 As it is, the two volumes into which it is proposed to compress the eighteen parts 

 will be ponderous enough. Three volumes, proportionately thinner, would appear 

 to us to be handier. 



The editor claims, in the introduction, to be supplying some long-felt wants in 

 British Bird literature. In conclusion we can only say that his claim is justified. 



Wm. Rowan. 



Class Book of Economic Entomology, with Special Reference to the Economic 

 Insects of the Northern United States and Canada. By William 

 Lockhead, B.A., M.S. [Pp. xiv + 436, with a frontispiece and 257 illus- 

 trations.] (Philadelphia: P. Blakiston's Son & Co., 1919. Price $2.50 net.) 



Economic entomology is a phase of the study of Insects that has come into 

 considerable prominence of late years. The more intense the exploitation of the 

 plant resources of a country becomes, the more evident it is that in agriculture, 

 horticulture, and forestry, more and more attention must be paid to the relations of 

 Insects and plants. The word Insects here needs a note of explanation, for those 

 included in the present volume, Wood Lice, Mites, Centipedes, Slugs, and Eel- 

 worms, are surely inclusive enough to satisfy the most rapacious entomologist. It 

 would.be pedantic to quibble over that, however, for nine-tenths of the pests are 

 true Hexapods, and the relations of these other forms to plants, the methods of 

 combating them, etc., are similar to those of the true Insects. 



The book is divided into four sections, the first treating of the anatomy, 

 morphology, life cycle, and economics of insects in general ; the second takes the 

 common crops and plants, describes the disease, and indicates the insect re- 

 sponsible ; the third treats of the classification, description, and identification of 

 common insects ; and the fourth deals with the methods of controlling them. 



As the author points out, the book is in the main a compilation from numerous 

 sources, as such a book must of necessity be, but it is none the less a valuable and 

 useful piece of work. The cross-references, the references to the sources of 

 information, glossary, index, to say nothing of the illustrations, will make it 

 invaluable in all courses on entomology in the area with which it deals. 



The book will save teachers and scholars much time, and the author well 

 merits their thanks. 



C. H. O'D. 



