754 



SCIENCE. 



[N. S. Vol. VIII. No. 204. 



volumed treatise upon zoology upon which 

 Professor Delage is at present engaged, and 

 which promises to become one of the monumen- 

 tal works of its kind. The present volume is 

 divided into four principal parts. The first 

 deals with the facts of observation, and dis- 

 cusses in a comprehensive manner the mor- 

 phology and physiology of the cell, of the in- 

 dividual, of degeneration, sex, correlation of 

 parts, death, etc., and, under the head of 'Race,' 

 the phenomena of heredity, variation and the 

 formation of species. The author has read 

 verj' widely and understandingly, and his ex- 

 position of the facts which he has to present is 

 extremely clear, so that this book easily occu- 

 pies a first place among those that must be con- 

 sulted upon the general phenomena of biology. 

 The second part discusses the special theories 

 which have been advanced by various writers 

 couerning the interpretation of the facts re- 

 ported in the first part. We find under this 

 head, for instance, the manifold views which 

 have been advanced concerning the interpreta- 

 tion of the karyokinetic figures, of the iso- 

 tropism of the ovum, of the germ plasm and of 

 telogeny. The third part discusses the general 

 theories, and here the author's industry is most 

 advantageously revealed, although, as it was but 

 natural to anticipate, the attention given to 

 French writers preponderates somewhat over 

 that accorded to the writers of other countries. 

 Here we find a historical review of the theories 

 which have been advanced concerning the soul, 

 formative force and the vital force, and a review 

 of the historic discussion between the Sperma- 

 tists and the Ovatists. We would direct atten- 

 tion especially to the review of the various 

 theories which have been put forward, begin- 

 ning with BufFon and continued by Darwin and 

 many others, according to which protoplasm is 

 supposed to contain units of living matter of 

 minute size, to which units the vital phenomena 

 are ultimately to be referred. Those who are 

 not familiar with the history of this subject 

 will be perhaps surprised to find how many and 

 varied these theories of the constitution of 

 protoplasm have been, and how slight a basis 

 of observation and fact any of them have had 

 for a foundation. The method In which the 

 author proceeds in these analyses is very excel- 



lent. He gives first a summary of the particu- 

 lar theory, and then presents his critical obser- 

 vations upon the evidence and character of the 

 theory itself, keeping thus his repertorial and 

 judicial functions entirely distinct. The fourth 

 part, which is the briefest, gives a review of the 

 entire series of conceptions which seem to the 

 author best founded and most coherent among 

 themselves with regard to the manifold prob- 

 lems of heredity and general biology. The 

 work closes with a valuable and very extensive 

 bibliography. The author has carried out his 

 purpose very successfully, and has produced a 

 work which ought to be available for consulta- 

 tion in every biological laboratory. 



Chakles S. Minot. 



Inorganic Chemistry according to the Periodic 

 Law. By F. P. Venable, University of 

 North Carolina, and Jas. Lewis Howe, 

 Washington and Lee University. Easton, 

 Pa., The Chemical Publishing Co. 1898. 

 Pp. 266. Price, $1.50. 



The authors of this text-book say in their 

 preface: "The claim made in behalf of this 

 book is that it takes the periodic system for its 

 guiding principle throughout ; * * * some 

 text-books give brief mention of the law ; others 

 introduce it partially while still clinging to the 

 old systems." How far the authors have de- 

 parted from the plan thus outlined is shown by 

 the table of contents. 



The introductory chapter occupies thirty one 

 pages. Molecules and atoms are treated on the 

 first page, the atomic theory on the second, the 

 gas laws and Avogadro's hypothesis on the fifth 

 and sixth ; valency and electro- chemical phe- 

 nomena on the sixteenth and seventeenth, the 

 periodic law on the eighteenth, MendelejeflT's 

 table and the reason for accepting it on the nine- 

 teenth. Absurd as it may seem to discuss these 

 topics before the simplest chemical fact has 

 been demonstrated, it is unavoidable if the gen- 

 eral plan of the book is carried out. In the 

 following chapters the elements (74 pp.), ha- 

 lides (11 pp.), oxides and sulphides (103 pp.), 

 nitrides, carbides, silicides and alloys (5 pp.), are 

 treated with reference to the periodic law. 



It must be remembered that this is an ele- 

 mentary text-book for beginners. The begin- 



