NA TURE 



553 



THURSDAY, APRIL ii, 1895. 



PHYSIOLOGY OF THE EXCITABLI: 

 TISSUES. 

 Elcctrophysiologie. Von VV. Biedermann, Professor der 

 Physiologic in Jena. (Jena: Fischer, 1895.) 



PROF. BIEDERMANN, who was not many years 

 ago promoted to the chair of Physiology at Jena, is 

 well known as having co-operated with Prof. Hering in a 

 very extended series of researches on the "general 

 physiology of muscle and nerve," of which the results 

 have been communicated to the Vienna Academy from 

 time to time during the last twenty years. The present 

 work will be welcomed by physiologists in the hope that 

 it will not only place at their disposal the rich harvest of 

 the author's persevering labours in this field of inquiry, 

 but that it will afford to him the opportunity of dealing 

 more completely than has hitherto been possible with 

 one of the most fundamental characteristics of the animal 

 organism — its power of responding in a specific way to 

 stimulation. This being, as we learn from the introduc- 

 tion, the purpose of the book, the title " Electrophysio- 

 logic " may seem scarcely suitable, for however intimate 

 and essential may be the relation between vital processes 

 and the electrical phenomena which accompany them, 

 these, after all, are only concomitants, and must be 

 thought of apart from the process itself. However this 

 may be, the author makes it quite clear that his scope is 

 not electrical, but purely physiological. Referring to the 

 " Muskel-physik" and the " Nerven-physiologie" of 

 Prof. Hermann, published in 1880, he declares it to be 

 his purpose to bring the subjects therein treated up to 

 date, and in doing so to follow the true physiological 

 method. 



" In morphology it is obvious that we must proceed 

 from the simple to the more complicated, but in physio- 

 logy . . . the opposite is in a certain sense the case. 

 Under the apparent simplicity of an amoeba manifold 

 physiological functions are latent.'' " The most various 

 duties are performed by the same protoplasm, whereas 

 in the higher animals each particular cell is devoted to 

 a specific function, and consequently affords a better sub- 

 ject of study than the protozoon, when the nature of that 

 function is to be determined." It is for this reason that 

 " our knowledge of contraction and of the processes 

 which are associated with it have been advanced in- 

 finitely more by muscle physiology than it ever could 

 have been by the microscopical e.xamination of the lower 

 organisms." (p. i.) 



The volume before us is the first part of a work which 

 is to include the whole of the physiology of the '" excitable 

 tissues." Its 440 pages relate directly to muscle, but 

 also comprise the electromotive properties of epithelial 

 and gland cells. In accordance with the general principle 

 that the study of structure must precede that of function, 

 the book opens with a very useful chapter of anatomical 

 prolegomena, in which, beginning with a section on the 

 contractile fibres of the stem of vorticella, the author 

 proceeds to the epithelial nerve-muscle cells of the 

 coelenterates, and so on to those of the worms. Then 

 conic in order the muscular elementsof .MoUusca (Lamelli- 

 N(l. 1328, VOL. 51] 



branchs and Gasteropods), of interest as showing the 

 striking relation of structure to physiological endowment. 

 Next we have before us the simplest forms of muscle- 

 cells in vertebrates, and finally the structure of striped 

 muscle, with reference to which we again find that 

 the relations between anatomical characteristics and 

 functions receive more attention than the endless 

 questions of histological detail which, in the minds of 

 most students, are associated with this subject. 



Of the 340 pages given to the physiology of muscle, 

 scarcely a third relate to its electrical properties. These 

 comprise four sections. The first and second deal with 

 the electromotive phenomena of muscle at rest and in 

 action ; the third relates to the so-called " positive 

 variation ' ; the fourth to secondary electromotive 

 actions. Throughout it is felt that Biedermann writes 

 as a physiologist, not as a physicist, availing himself of 

 the best physical methods to investigate phenomena, 

 but regarding them not as the thing itself, but merely as 

 indications, by the aid of which the time and place rela- 

 tions of vital processes become known to us. In this 

 tendency to take things as they are, postponing 

 theoretical speculations, until the results of the more 

 exact methods of observation which we are now only 

 beginning to know how to use, have been systematised, 

 Biedermann is happily at one with all the leaders of 

 thought and work in this field of inquiry. 



Among the most interesting of the observations by 

 which Prof. Biedermann has contributed to the advance 

 of what may, in the truest sense, be called elementary 

 physiology, are those by which, in co-operation with his 

 master, and, it may be added, in language not unfamiliar 

 to English students, he has sought to work out that 

 notion of ana anA ca/a, or of A and D, as Hering puts 

 it, in accordance with which the influences exercised by 

 one part of the organism on another through the nervous 

 system, are regarded as manifestations of two antagon- 

 istic tendencies, the one quelling, the other e.xciting in its 

 nature. This principle, which Prof Hering first invoked 

 to explain certain antagonisms relating to the perception 

 of colour, has served Biedermann as a guide in the 

 study-'of similar antagonisms in the behaviour of muscles, 

 and he has furnished us with several instances showing 

 that in the responses of muscles to the stimulation of 

 their nerves, we may have to do not with spur only, but 

 with a mixture of spur and bridle, a co-operation of 

 quelling and exciting influences conveyed to the re- 

 sponding muscle by the same channel — its motor nerve. 

 In Biedermann's very interesting third section, the 

 reader will find this subject fully discussed. The gist of 

 what he has observed is as follows : — The change of 

 form by which a muscle responds to stimulation of its 

 nerve is not always, as is ordinarily the case, of the 

 nature of shortening or contraction. Under certain well- 

 ascertained conditions the " normal " eflfect is reversed : 

 the muscle relaxes. By comparison of the instances 

 in which this happens, we learn that the anomaly (it 

 we are to call it so) depends on the terminal organ, 

 not on the nature of the stimulus, or on the channel by 

 which it is conducted. For it is found that muscles 

 which normally exhibit no tendency to respond by re- 

 laxation, acquire that tendency when they have under- 

 gone " modification,' either by the persistent action of 



B B 



