214 W. C. ALLEE AND SHIRO TASHIRO 



the shorter the survival time in the cyanide, hence the resis- 

 tance of isopods to potassium cyanide is a fair measure of their 

 metabolic activity (page 207). 



2. The calcium ion decreases the carbon dioxide production 

 in the isopods and renders them less positive in their rheotactic 

 reactions (page 209). 



3. There is a high degree of similarity between the variation 

 of carbon dioxide production of individual isopods and their 

 rheotactic reaction (page 211). 



4. The rheotactic reaction is an expression of the relative 

 metabolic activity of the animal under the conditions to which 

 it is acclimated for the time being. 



January, 1914. 



LITERATURE CITED 



Allee, W. C. An experimental analysis of the relation between physiological 



1912. states and rheotaxis in Isopoda. Jour. Exp. Zool., vol. 13, pp. 

 269-344. 



1913. Further studies on physiological states and rheotaxis in Isopoda. 



Ibid., vol. 15, pp. 257-295. 



1914. Certain relations between rheotaxis and resistance to potassium cyanide 



in Isopoda. Ibid., vol. 16, no. 3. 

 Child, C. M. Studies on the dynamics of morphogenesis and inheritance in experi- 

 1913. mental reproduction. V. The relation between resistance to depress- 

 ing agents and the rate of metabolism in Planaria dorotocephala and 

 its value as a method of investigation. Ibid., vol. 14, pp. 153-206. 

 1913a. Certain dynamic factors in experimental reproduction and their signif- 

 icance for problems of reproduction and development. Arch. Entw. 

 Mech., Bd. 35, pp. 598-641. 

 Tashiro, Shiro Carbon dioxide production from nerve fibers when resting and 



1913. when stimulated; a contribution to the chemical basis of irrita- 

 bility. Amer. Jour. Physiol., vol. 32, pp. 107-136. 



1913a. A new method and apparatus for the estimation of exceedingly minute 

 quantities of carbon dioxide. Ibid., vol. 32, pp. 137-145. 



1914. Carbon dioxide apparatus III. Another special apparatus for the 



estimation of exceedingly minute quantities of carbon dioxide. Jour. 

 Biochem., vol. 16, pp. 485-494. 



