_574 J- Frank Daniel 



learned much of the real nature of the relation that alcohol bears 

 to the process of metabolism. The former notion that alcohol 

 facilitated the storing up of fat by retarding metabolism has largely 

 given place to the view that alcohol is itself oxidized in the body, 

 thus preventing or retarding the oxidation of other materials. 

 Further than the fact of its oxidation but little is known. 



In the following investigations I have undertaken a study of 

 the general effects of alcohol upon single-celled organisms. For 

 work of this sort much depends upon the type of cell selected. 

 Probably no single requisite is more important than that the organ- 

 ism be of sufficient size to permit ready determination of the 

 moment of death. The blue Stentor (S. coeruleus) meets this 

 requirement admirably. In addition, its habit of attachment 

 gives it a marked advantage over more active infusoria, and its 

 characteristic reaction to light makes it easily obtainable in larger 

 numbers relatively free from debris. 



In determining the fatal dose of alcohol for Stentor it will be 

 well briefly to survey the efi^ects of weak percentages in general. 



II PRELIMINARY EXPERIMENTS 



A Effects of Minimal Amounts of Alcohol 



Alcohol even in very low percentages is generally regarded as a 

 "protoplasmic poison." Its deleterious effects in small doses 

 depend much, however, upon the kind of organism studied. 



Hodge^ in experimenting upon developing yeast found a de- 

 crease in division, in solutions containing as low as y^o of i per 

 cent of alcohol, the average number of cells in this strength being 

 only 992 per cubic centimeter as compared with 2061 under nor- 

 mal conditions. On the other hand Maltaux and Massart^ for 

 Chilomonas, and Woodruff" for "one period of the life cycle" in 

 Paramecium have shown that alcohol increases the division rate. 

 In Paramecium it is further important to note that the increase 

 was lost after a time. 



7 Hodge, 1897, Pop. Sci. Monthly, vol. 1, pp. 594-603. 



* Maltaux, Marie et Massart, Jean. 1906, Recueil de I'Institut Botanique, vi, pp. 269-421. 



9 Woodruff, L. L., 1908, Biol. Bull., x\-, pp. 85-104. 



