SAMUEL BRODY 437 



SUMMARY. 



The rate of ovulation of the domestic fowl may be expressed by the 

 equation of an autocatalytic chemical reaction. This is not surpris- 

 ing in view of the fact that the rate of growth may also be expressed 

 by such an equation, and that the rate of ovulation is probably an 

 index of the growth of the eggs. This brings the phenomenon of 

 ovulation in the hen under the general subject of growth, and sub- 

 stantiates the generality and the probabiUty of the hypothesis that 

 growth, or at any rate the limiting factor of growth, is an autocata- 

 lytic reaction. 



The idea of applying the equation of growth to the rate of ovula- 

 tion in the fowl suggested itself while studying the rate of growth of 

 the dairy cow with Mr. A. C. Ragsdale, Chairman of the Department 

 of Dairy Husbandry. I take pleasure in expressing my apprecia- 

 tion to Mr. Ragsdale, and Mr. H. L. Kempster, Chairman of the 

 Department of Poultry Husbandry in this station, for their encour- 

 agement. 



