768 



RATE OF GROWTH OF DOMESTIC FOWL 



somewhere between 24 and 28 weeks^ of age when growth of non-fatty 

 tissues probably ceases. That each of these postembryonic cycles 

 follows the equation of an autocatalytic monomolecular reaction 

 can be seen from their shape. This can be easily verified by taking 

 ti, the age of maximum growth at 8.5 weeks, and following the tech- 

 nique of computation described in the preceding paper on the growth 

 of the dairy cow, we obtain the equation 



Log 



2.76 



= 0.182 - 8.5) 



which gives calculated values closely agreeing with the observed 

 weights. 



Essentially similar results were obtained with other breeds of fowl 

 such as the White Leghorn,'^ single comb White Leghorn,'' and White 

 Plymouth Rocks, ^ the several breeds differing only with respect 

 to the several constants. From Fig. 2 it is clear that the equation 

 will also hold somewhat less accurately for the second cycle with 

 a maximum at 18 weeks. 



7 Lamon, H. M., and Lee, A. R., U. S. Dept. Agric, Bull 561, 1917, 37. 



8 Phillips, A. G., Purdue Univ. Agric. Exp. Station, Bull. 1906, 1916; Purdue 

 Univ. Agric. E.xp. Stntion, Bull. 214, 1918. 



