376 Physiologie. 



The experimental work involved was done at Woods Hole in 

 1911 on Arenicola larvae. It was found that various anaesthetics 

 such as ether, Chloroform, ethyl alcohol, chloretone, chloral hydrate, 

 benzol, etc. prevent or check the stimulating and permeabilit}'- 

 increasing action of NaCl solations, but to different degrees. This 

 hindering effect was less pronounced in the case of KCl Solutions? 

 The toxic action of NaCl and KCl is also retarded by anaesthetics. 

 A theoretical discussion of several pages is given. It is concluded 

 that, granting that Stimulation involves an increase of surface per- 

 meability, the degree of electrical polarization of the plasma mem- 

 brane determines its permeability, depolarization corresponding to 

 or giving increased permeability. In general, anaesthetic action is 

 believed to consist in an alteration of the plasma membrane in 

 such a way as to check or prevent increase in ionic permeability, 

 and that this is accomplished by an increase in volume of the 

 lipoid particles of the membrane. M. C. Merrill (St. Louis). 



Lillie, R. S., Antagonism between salts and anaesthe- 

 tics. IL Decrease by anaesthetics in the rate of toxic 

 action of pure isotonic salt Solutions on unfertilized 

 starfish and sea-urchin eggs. (Amer. Journ. Physiol. XXX. 

 p. 1—17. 1912.) 



This paper considers some work done at Woods Hole in 1911. 

 Unfertilized eggs of starfish and sea-urchins were used. In general 

 the results obtained were the same as those with Arenicola larvae, 

 and the explanation and theory advanced are likewise the same. 

 It was found, however, that in the case of salt Solutions whose 

 toxic action was gradual instead of rapid that anaesthetics have 

 little or no antitoxic effect. These experiments and those previously 

 reported are considered by the author as definitely indicating the 

 existence of lipoids as essential constituents of the membranes, and 

 he emphasizes that point. It is also suggested that lipoids have a 

 "protective" relation to the other colloids of the corresponding pot- 

 assium salts, yet in the presence of CaClg the relations are reversed. 

 Calcium greatly decreases the toxicity of sodium but only slightly 

 that of potassium. KCN decreases the toxicity of sodium but increa- 

 ses that of potassium. This fact is unexplained. 



M. C. Merrill (St. Louis). 



Lillie, R. S., Antagonism between salts and anaesthe- 

 tics. III. Further observations showing paralell de- 

 crease in the stimulating, permeability-increasing, 

 and toxic actions of salt Solutions in the presence of 

 anaesthetics. (Amer. Journ. Physiol. XXXI. p. 255—287. 1913.) 



This paper is a continuation of previous ones along the same 

 line. An extended theoretical discussion is given regarding anaesthesia 

 and its relation to permeability, the plasma membrane, electrical 

 phenomena, etc. For the experimental work the larvae of Arenicola 

 were used and these were treated with . 55 N . NaCl containing the 

 anaesthetic in known concentration. A considerable number of 

 anaesthetics was used belonging to various classes: alcohols, esters, 

 hydrocarbons and miscellaneous Compounds. In general all the 

 anaesthetics tried gave rapid cytolysis in strong concentrations but 

 anti-cytolytic action in weaker Solution. They showed a definite 



