210 ANNALS OF SCOTTISH NATURAL HISTORY 



hope that the whole of the Supplement will appear at short intervals, 

 and that the text throughout will be up to date, without requiring 

 in its turn to be supplemented even before its issue. 



Outlines of Zoology. By J. Arthur Thomson, M.A. (Edin- 

 burgh : Young Pentland, 1892.) 



The announcement of a new textbook of Zoology is at the present 

 day perhaps scarcely an event of sufficient novelty to attract more 

 than passing notice, unless it bears the stamp of a master of the 

 subject. The work before us, however, is decidedly above the average, 

 and when its numerous excellent qualities become known, will 

 doubtless attain the rank it deserves. Perhaps the most conspicuous 

 feature of the book (one which will make it specially useful to 

 students of Biology) is the addition of a description of some well- 

 known type to the account of each group of animals — the types 

 selected being in most cases those included in the zoological 

 curriculum of the various universities. As everybody knows, the 

 " type system " of study has in recent years been carried to an excess 

 which is unfortunately resulting in the creation of an ever-increasing 

 number of worthless cram-books, which cannot be too strongly 

 condemned. Mr. Thomson, however, makes use of the " type " 

 merely as a supplement to the general account of the class to which 

 it belongs — a method of treatment which is to be highly commended, 

 for the type-system when thus employed must be approved of by 

 every one. The first seven chapters constitute a general "intro- 

 duction " and deal with a variety of subjects, such as the general 

 classification of the Animal Kingdom, the histology of tissues, 

 the functions of organs and tissues, development, the past history 

 of animals, geographical distribution and evolution. The re- 

 maining chapters — viz. viii. to xxv. — deal with the different classes of 

 animals ; the general characters in each case preceding the detailed 

 description of the type. There is something unusually attractive 

 about the style of the book throughout, and in almost every chapter 

 we meet with interesting and useful information of a kind not usually 

 met with in textbooks of this description. For example, we are 

 supplied with concise accounts of such subjects as the inter-relations 

 of animals and plants, the " courtship " of animals, the migration 

 of birds, parasitism, sexual selection, the protective devices of 

 animals, and a host of other facts concerning the habits of animals 

 of which the student is usually left in ignorance. Great care has 

 evidently been expended in bringing the book thoroughly " up to 

 date " in every department, and we are glad to see that the sources 

 of the more important recent " views " are given, for this is always 

 very acceptable information to advanced students, and too frequently 

 omitted. 



The illustrations are not so good (from an artistic point of view) 

 as we should like to see, and we think they might be multiplied with 



