NOTICES OF NEW BOOKS. 



237 



Prof. Bateson has described a mass of accurate observation 

 and experiment, which fully entitles him to remark that " no 

 one who is acquainted with Mendelian method will doubt that by 

 its use practical breeders of animals and plants may benefit." 

 At the same time this volume very considerably advances our 

 conception of organic evolution, and will well repay the careful 

 study and consideration of all who are interested in that great 

 problem. There is still much to be done by the Mendelian 

 method, the results of which may exceed reasonable expectation, 

 and we gather from the pages of this book that in Cambridge 

 alone there are enthusiastic workers, and of both sexes, who are 

 energetically pursuing the investigation. 



A Student's Text-Book of Zoology. By Adam Sedgwick, M.A., 

 F.R.S. Vol. iii. Swan Sonneschein & Co., Ltd. 



We welcome the third volume of this authoritative work on 

 Zoology, which completes the Special Parts, and Prof. Sedgwick 

 tells us that he is now in a position to turn his attention to the 

 General Part. The second volume was noticed in * The Zoolo- 

 gist ' for 1905, so that the work cannot be described as hurried 

 through the press. In this volume the chapters on Tunicata, 

 Enteropneusta, Echinodermata, Onychophora, and Myriapoda 

 are by the author ; those on Arthropoda in General and on the 

 Crustacea, and the section on the Xiphosura, are by Mr. Lister ; 

 those on the Insects and Arachnida being contributed by Mr. 

 Shipley. That the order of the Phyla is not one universally 

 followed — the Arthropoda being treated last — is discussed in the 

 Preface, and, as Prof. Sedgwick remarks, " all zoological arrange- 

 ments are compromises, and none of them can be, now or ever, 

 entirely natural." 



In his treatment of the Insecta, Mr. Shipley has not followed 

 the sequence of Dr. Sharp in the Cambridge Natural History, of 

 which he is a co-editor, but in this arrangement there is at 

 present, and rightly, no finality. We still have much to learn 

 on this question. At present — at least in this country — the 

 dominant entomological drift is apparently towards speculative 

 questions on the subject of mimicry, the evolutionary study by 

 practical or morphological methods being in some desuetude. 



