5 i6 SCIENCE PROGRESS. 



There appeared last year a paper by Biedermann in 

 which the electrical phenomena in several cases of mucous 

 glands are detailed, and the results are apparently so con- 

 sonant in all the structures investigated, that the work not 

 only carries considerable weight, but the theory of action 

 deduced by the author must certainly rank as one of the 

 best put forward, especially as it tends, in one case, that of 

 the frog's skin, to reconcile some of the opposing results 

 obtained by Roeber and Engelmann on the one hand and 

 Hermann on the other. 



The experiments deal with mucous glands, either multi- 

 cellular as in the tongue and skin of the frog, or unicellular 

 (goblet cells) as in the pharyngeal and cloacal mucosas of the 

 same animal. 



Bohlen under Biedermann's direction has continued the 

 work in the case of the gastric mucosae of the frog and 

 certain mammals. 



It is convenient and conducive to brevity to first sketch 

 Biedermann's theory before stating the facts upon which it 

 is built. 



Biedermann, adopting Hering's extension of the altera- 

 tion theory, viz., that alterations in metabolism rather than 

 of chemical composition in protoplasmic continuity, lie at the 

 root of vital electrical changes, points out that in the gland 

 cell we have a structure pre-eminently liable to variations 

 from the balance between constructive and destructive 

 events. That part of the protoplasm of the cell engaged in 

 the elaboration of the secretory products, though ordinarily 

 the seat of an excess of katabolic over anabolic activity, 

 must at the same time be in a highly unstable state and 

 liable under certain conditions to an overthrow of balance 

 to the opposite side. 



action of the drug is not that the flow of fluid in the cells is completely 

 stayed, so that the whole variation is produced by the " metabolic events," 

 but rather that, since according to his results all cell activities are equally 

 acted upon by atropine, in cases of slight cell action, in highly poisoned 

 but not paralysed states, the flow of fluid is proportionately more cut down 

 than the series of metabolic events, which Bayliss and Bradford consider 

 are the cause of the ingoing current. 



