APPENDIX I. 



NOTICES OF BOOKS. 



Allgemeine Physiologic Ein Grundriss der Lehre vom Leben. Von Max Verworn. Jena : 



Gustav Fischer, 1895. 



This volume of 571 pages must find a place in the library of every serious student of 

 Nature, for it marks the renaissance of Comparative Physiology. The study of functions, and 

 of structure in relation to the functions, of living plants, animals, and protists, are duly 

 considered, and an attempt is thereupon made to widen the physiological horizon. The 

 kymograph and spirometer would appear to be the author's betes noires, and of his 268 

 illustrations, but 10 are tracings and spectral charts, and less than 50 are delineations of 

 apparatus (and those of the simplest possible kind). The rest, with few exceptions, depict 

 living objects and phases of observed activities. The book opens with a Preface, in which the 

 author confesses to an aspiration to a literary style that may appeal to persons beyond the mere 

 craftsmen ; and there follows a Historical Sketch, in which the pioneer work of Johannes 

 Miiller, to whose memory the book is befittingly dedicated, receives full recognition. Then 

 there follow, in order, Special Chapters devoted to The Constitution and Properties of Living 

 Matter, to Metabolism and Change of Form, The General Conditions of Life, to Stimuli and 

 their Effects, and The Mechanism of Life. The History and Rationale of Life, Cell-division, 

 Reproduction, and Death, are incidentally considered. A considerable portion of the 

 work is devoted to a description and discussion, with extension, of the author's well-known 

 observations upon living protozoa and on the behaviour of the nucleus during functional 

 change. The nucleus is brought into special prominence in relation to protoplasmic move- 

 ment, the movement of contraction being interpreted as probably due to nuclear attraction. 

 The more important among recent investigations are incorporated, and we note with satisfaction 

 those of Hodge upon the metabolism of the nerve-cell, and of Dreyer and Schulze upon 

 skeletogenesis in the Invertebrata, so fully borne out by the later work of Theel and 

 Kishinouye. 



The key to the author's attitude lies in his formidable declamation against the physiological 

 methods of to-day, as inadequate to explain the simplest processes of life. The many and 

 ingenious comparisons between the parts of the animate body and of an inanimate machine, so 

 recently enforced, are now untenable. To take a hackneyed example, the discovery that during 

 the passage of visual stimuli there is a contraction of the retinal pigment, bearing a definite 

 relationship to the colours of the spectrum, 1 and that the image formed by reflection from the 

 posterior face of the crystalline lens comes to a focus within that bod)', - undermine the 

 fascinating comparison of the eye with the photographer's camera. And when we consider, for 

 example, that the evolution of carbonic acid by a living muscle is not a simple respiratory 

 process, but one that under the action of a stimulus may go on in an atmosphere of nitrogen, 

 that the absorption of oxygen by blood does not follow the general law of absorption according 

 to pressure, and that the removal of assimilable food through the intestinal wall does not take 

 place according to the laws deduced from the study of an ordinary diffusion septum, it becomes 

 only too apparent that directly we come into touch with the animate a something has to be 

 reckoned with, which the laws thus far deduced from the study of the inanimate will not explain. 

 What is it that this neo-vitalism presents to us? Is it the Psyche of the ancients over again — 

 a something beyond our discovery or comprehension ? or is it a problem in molecular 

 physics ? Most assuredly the latter, but not that of the inanimate as thus far understood. 

 The time has come when to the study of the processes of life something more than the application 

 of the methods of the physicist and chemist of to-day to the mere study of organs and tissues 

 must be applied. An entirely new field lies before us. Physiologists have long reminded us 

 that the mystery of life lies hidden in the unicellular organisms, but they have been too fully 

 content to allow their studies to centre in the applied branches of their science. By physiology 



1 Angelucci. Moleschott's Untersuchg. z. Naturlehre, bd. xiv. , hf, 3. 



2 Boys. Phil. Mag. (ser. 5), vo'. xiv., p. 40. 



D 



