1897.] Recent Literature. 517 
the study of insects in general. For convenience the author adopts 
the following system of classification, viz.: Coleoptera (including Strep- 
siptera), Orthoptera (including Euplexoptera and Dictyoptera), Neurop- 
tera (including Trichoptera, Thysanura, Collembola, Mallophaga and 
Thysanoptera), Hymenoptera, Lepidoptera, Hemiptera (including the 
sub-orders Hemiptera-Heteroptera and Hemiptera-Homoptera, and the 
Anoplura), and Diptera (including Aphaniptera, and possibly Achrei- 
optera). 
After an introduction concerning insects in general, Mr. Kirby 
takes up each Order in turn, giving an account of its principal Famil- 
ies, with observations on their habits and economic importance. Many 
typical species are described and figured, so that it is comparatively 
easy for the student to identify the principal divisions. 
A complete index adds to the usefulness of the book. 
The work is necessarily of a very general character, and is well- 
adapted to serve as an introduction to a fascinating science. 
Birds of Illinois.‘—The Natural History Survey of Illinois has 
published its second volume, part I, a continuation of the descriptive 
catalogue of the birds of that State, by Robert Ridgway. The Orders 
treated of in the present volume are the Gallinz, Limicole, Alector- 
ides, Herodiones, Anseres, Steganopodes, Longipennes and Pygopodes. 
Thirty-three full page plates give the heads, feet and legs of charac- 
teristic types of the Orders 
Mr. Ridgway’s well- known competency in this field insures the value 
of the work. 
The Forces of Nature.’—A small octavo, of some 150 pages, in 
which are briefly stated the fundamental principles of the laws which 
govern the operations of nature. Part I contains five chapters treat- 
ing respectively of the solar system, sound, structure of matter, radiant 
energy and electricity. Part II comprises a series of disconnected 
paragraphs, giving the latest discoveries in the physical sciences. This 
-volume is at all odds the most semontary treatise on the subject that 
could have been devised. 
* The Ornithology of Illinois. By Robert Ridgway. Natural History Survey 
of Illinois, Vol. II, Pt. I, Springfield, 1895. : 
5 The Forces of Nature. By H. B. Harrop and L. A. Wallis. Columbus, Ohio, 
1895. 
