2344 Journal of Applied Microscopy 



GENERAL PHYSIOLOGY. 



RAYMOND PEARL, University of Michigan. 



Books and Papers for Review should be Sent to Raymond Pearl, Zoological Laboratory, 

 University of Michigan, Ann Arbor, Mich. 



Verworn, M. Die Biogenhypothese. Eine This book is an expansion o£ the theory 



kritisch-experimentelle Studie liber Vor- r ^, r ^ , i i ■ i • i i 



giinge iu der lebendigen Substanz. Jena of the fundamental physiological baslS 

 (Gustav Fischer), 1903. Pp. iv and 114. of vital phenomena first sketched in 



outline in the author's well known 

 " AUgemeine Physiologic." The theory is advanced merely as a working 

 hypothesis, and regarded in this light it will be found extremely suggestive by 

 all biologists. By the term " Biogen " the author designates the chemical sub- 

 stance in protoplasm by whose metabolism (both destructive and constructive) 

 vital phenomena are produced. At the outstart a detailed comparison between 

 the catalytic action of enzymes and the metabolic processes taking place in liv- 

 ing substance is made, and the conclusion reached that the biogen molecule may 

 be regarded as very similar to an enzyme. On the basis of various experimental 

 facts the following composition is suggested for the biogen molecule : as the 

 center and basis of the molecule we may have a nitrogenous compound of the 

 character of a benzol group. With this central group are associated two side- 

 chains ; one a compound of the carbohydrate type with a terminal aldehyde 

 group, the other a nitrogenous or iron compound. In the first of these side- 

 chains the processes of oxidation are believed to occur, while the second acts as 

 a receptor and translator of oxygen. With this idea as a basis the author pro- 

 ceeds to discuss a number of the most important physiological problems, such 

 as metabolism, the phenomena of the action of stimuli, the source of the energy 

 of muscles, etc. Lack of space forbids further mention of this very interesting 

 contribution to physiological theory, which is well worth the perusal of every 

 biologist interested in the fundamental problems of his subject. r. p. 



I :ii:^ DC r\ T^cc • .1. T-1 • , It is well known that the particles of a 



Lillie, R. S. On Differences in the Electrical ^ 



Convection of Certain Free Cells and colloidal solution move towards and 

 Nuclei. Amer. Jour. Physiol. 8: 273-283, aggregate at the poles when a constant 



electric current is passed through the 

 solution. The pole to which a particular particle shall go is determined by the 

 sign of the electric charge which that particle bears. Furthermore, the sign of 

 the charge bears a definite relation to the chemical nature of the colloidal sub- 

 stance, acid particles being electrically negative and basic particles positive. In 

 the cell the chromatin of the nucleus is strongly acid, while the cytoplasmic pro- 

 teids are for the most part basic in character. On the basis of the results 

 obtained with colloidal solutions it would then be expected that nucleus and cyto- 

 plasm differ electrically. The purpose of the present paper is to test experi- 

 mentally this supposition and to point out its importance for general theories of 

 the physiology of the cell, mitosis, etc. The experimental method used was to 



