176 THE ENTOMOLOGIST. 



RECENT LITERATURE. 



H. KoLBE, " Gartenfeinde und Gartenfreunde, die fiir den Gartenbau 

 scluidliclieii und niitzlicben Lebeweseu." Gartenbau Bibliotek, 

 Band 34-36 ; pp. 1-320, and 76 text figures. Karl Siegismund, 

 Berlin (preface dated June, 1901). 



This useful little book may be compared best, perhaps, with Dr. 

 John B. Smith's ' Economic Entomology ' (1896). The arrangement, 

 however, is quite different, the present work discussing the pests under 

 the heading of their food-plants, instead of in systematic order. 



After an introduction upon the structure of the insect frame, and 

 an account of the principal economic orders and families, with analy- 

 tical tables for their further identification, preventive measures and 

 remedies are briefly discussed. The more important plants are next 

 considered, with an account under each of their various pests, viz, 

 divers fruit-trees, strawberries, vegetables, and ornamental shrubs ; a 

 considerable amount of otherwise scattered information is here gathered 

 together. The second part deals with the gardener's friends — beasts, 

 birds, ichneumon-flies and others. 



The author's name is a guarantee of the accuracy of the entomo- 

 logy, while the illustrations, most of which are from the pencil of 

 Dr. Riibsaamen, are clear and well-selected. The book is plainly but 

 substantially "got up," and the printing (which is in the German 

 character) is wonderfully clear. G. W. K. 



A. D. Michael, " British Tyroglyphidse," vol. i. pp. v and 291 ; 

 19 partly coloured plates (Ray Society, 1901). 



A COMPANION volume to the author's " Oribatidae," and deals with 

 the Acari of which the " Cheesemites" are the type. 



This first volume contains a history of the literature ; criticism on 

 recent classifications of the Acarina ; followed by detailed accounts of 

 the anatomy and development, and a systematic account of a portion of 

 the family. In the forthcoming second volume we are promised the con- 

 tinuation of the systematic account and a bibliography of the literature. 



Although so minute — one thirtieth of an inch being the length of 

 a very large species — the Tyroglyphidae are of considerable importance. 

 The number of known species is very few, some fifty being recognized, 

 and these mostly very widely distributed ; yet many of them " swarm 

 in such countless myriads . . . that the mind shrinks from any 

 attempt to estimate their numbers, even in a small space." They are 

 enormously destructive to cheese, flour, hay, and druggists' stores ; 

 sound healthy bulbs as well as rotten ones, and dried fruits, attest their 

 ravaging powers. Biologically, however, the Tyroglyphidfe are spe- 

 cially remarkable for the possession of a " Hijpopus-staige." The 

 " Hypopi " are heteromorphous— comparatively rarely occurring — 

 nymphs (of both sexes) which are not true parasites, but only attach 

 themselves to any suitable moving creature for purposes of transit. 

 This Hypopm-stsige was for long an enigma, but was elucidated by the 

 author in 1885, and is now fully discussed in the sixth chapter. We 

 must not omit mention of the nineteen plates containing 241 beautiful 

 drawings by the author, of which forty-five are coloured. They are 

 beyond all praise. G, \V. K. 



