702 



SCIENCE. 



[N. S. Vol. XVII. No. 435. 



dearth of observations which may be expected 

 to throw light on the chemical reactions and 

 metabolic processes of the lower animals; but 

 they are scattered so widely through the lit- 

 erature, and they appear so isolated in their 

 bearing, that an adequate systematic presen- 

 tation of the comparative chemistry of ani- 

 mals has never been attempted before the 

 publication of the book by Dr. von Fiirth. 

 Indeed, it must be acknowledged that few 

 individuals have acquired the wide biological 

 experience and chemical training which are 

 demanded for the successful accomplishment 

 of such a task. 



In the opinion of the writer, Dr. von 

 Fiirth's book is one of the most important 

 recent additions to the literature of physio- 

 logical chemistry. Its value lies not only in 

 the compilation of an orderly digest of an 

 enormous number of scientific papers, most 

 of which have apparently been consulted in 

 the original; equally satisfactory is the crit- 

 ical attitude which has been assumed in edit- 

 ing the heterogeneous experimental material. 

 And it is, perhaps, not so much in the classi-*" 

 fication of facts and the orderly treatise on 

 comparative physiological chemistry, as in 

 the exposition of the deficiencies of our 

 knowledge, that, the biological investigator 

 will find the work helpful and stimulating. 

 In almost every chapter the author has pointed 

 out lines of experimental inquiry — ^biochemical 

 problems which demand solution. What has 

 already been attained makes it clear that we 

 may expect still greater advances in biology 

 to follow the more extensive application of 

 comparative chemical methods in this domain. 

 A review of the current text-books will readily 

 convince one upon what slender basis many 

 chemical considerations, handed down without 

 verification from writer to writer, really rest. 

 As von Fiirth remarks, too many have con- 

 tented themselves with the principle: 



" Nur muss man sich nicht allzu angstlieh qualen; 

 Benn eben wo Begriffe fehlen. 

 Da stellt ein Wort zur rechten Zeit sich ein. 

 Mit Worten lasst sich treflBich streiten, 

 Mit Worten ein System bereiten, 

 An Worte liisst sich trefHich glauben. 

 Von einem Wort liisst sich kein Iota rauben." 



New experiments and fresh facts are 

 wanted; and the encouragement which this 

 volume offers will bring results. When, for 

 example, the physiological chemist shall be 

 able to differentiate the proteid substances 

 according to their chemical structure — a pos- 

 sibility which recent advances make by no 

 means improbable — then we may truly group 

 like with like and classify protoplasmic masses 

 according to their chemical make-up. Then 

 we may hope to accomplish along chemical 

 lines also what the morphologists have long 

 attempted with much success in determining 

 the biological relationships of animals. In 

 merely pointing out the gaps in our present 

 knowledge von Fiirth has done a useful service. 



Von Fiirth's book is not adapted to detailed 

 review in this place. In an introductory 

 chapter a resume of the essential features of 

 organic chemistry and of the physiologically 

 important types of organic compounds has 

 been given with unusual success. This will 

 be a welcome recapitulation to the biologist 

 unaccustomed to thinking in chemical ways. 

 Succeeding parts deal with the chemical com- 

 position of protoplasm, the blood, respiration, 

 nutrition, excretion, animal poisons, specific 

 secretions, the muscles, the connective tissues, 

 reserve and skeletal constituents, products of 

 the sexual glands, and the chemical environ- 

 ment of animals. In each chapter an intro- 

 ductory historical sketch leads to detailed con- 

 sideration of the topic in connection with the 

 various groups of the invertebrates. The ref- 

 erences to the literature are given in detail, 

 experimental methods being included in many 

 cases. 



The completion of a task such as von Fiirth 

 has accomplished so well should not be made 

 the occasion for unfavorable criticism. A 

 number of typographical errors, aside from 

 those noted in the appendix, remain uncor- 

 rected. It seems unfortunate that in Strass- 

 burg the work of American physiologists is 

 still cited and known only through German 

 abstracts. Dr. von Fiirth deserves congratu- 

 lation for his eontribiition to biochemical 

 literature. Lafayette B. Mendel. 



Sheffield Scientific School, 

 Yale University. 



