149 



witli the inoKt ferocious ants, and further, tliat we have a multitude of 

 case-bearing- Clirysonielidic (Cryi>toc<'])lialus and allied jicnera) which 

 do not live with ants. There is little or nothing;" known regarding the 

 relatioushii) of the myrniecophilous Chrysouielids to their hosts, but it 

 is safe to say that the ])resence of these inquilines is not in any way 

 injurious or annoying to the ants, and that the behavior of the latter 

 toward the former is friendly, or at least indifferent. 



A COMPENDIUM OF ECONOMIC ZOOLOGY.* 



The European literature is rich in more or less useful manuals of 

 injurious or beneticial animals of one class or another, but we do not 

 remember having- seen a recent work which covers the whole domain of 

 economic zoology in so complete a manner as that which has just been 

 published by Dr. J. Ritzema Bos, professor in the Agricultural College 

 at Wageningen, and ujhui a perusal of this well-illustrated ])0]»ular 

 work we are convinced that it will be extremely useful not onl> to the 

 farmer, gardener, and forester of Germany, for whom it is ])rimarily 

 intended, but also to all interested in the economy of animals. The 

 nearest approach to this volume which has been i)ublished of late is 

 Raillet's Zoologie M^dicale et Agricole (Paris, 1886), but this deals more 

 with the medical side of the subject. 



The inii»ortance of entomology to agriculture in its widest sense 

 becomes very apparent from this work, for the insects alone (although 

 only those of centi'al Europe are treated) occupy more than one-half of 

 the 827 pages of the volume. Some families toward the end of the ento- 

 mological portions are treated very inadequately, e. //., the Coccidse get 

 only two pages ; the Pediculi and Mallophaga combined occupy but 

 little more than one page; and the Arachnida are not alluded to at all 

 among the beneficial animals. The Insecta are generally treated in the 

 customary sequence of the orders and families, each of them having a 

 short introduction on general characteristics and development. In 

 Lepidoptera, however, the vast number of injurious caterpillars of all 

 families are divided primarily according to the food-plants and other 

 objects they attack. The clothes-moths are strangely enough omit- 

 ted. In the large divisions ''deciduous trees" and "coniferous trees" 

 further subdivisions are made: tirst, according to the mode of attack 

 (buds, trunk, leaves, etc.), and secondarily, according to structural 

 characters of the cateri>illars. This lenders the whole arrangement 

 somewhat awkward and confusing to the untrained reader in si)ite of 

 the references and cross-references given in numbers. The Scolytidae, 

 Tenthredinida', and Aphidida' are treated in the ali)habetical secpience 

 of food-plants, and here the arrangement is quite ])ers])icu<)us. 



The condensation of the life-histories is admirably done, and the 

 author has not only used the literature but has added largely tiom his 



' Thierische Schadlinge iind Nutzlinge flir Ackerbau, Viehzucht, Wald- imd Gar- 

 tenban, von Dr. J. Eitzema Bos, Berlin (Paul Parey, )1891. 



