1094 PROTEIN METABOLISM [pt. iii 



The data of Fiske & Boyden and of Needham, when plotted in terms 

 of milligrams of protein combusted each day by lOO gm. dry weight 

 of embryo, show the peak in both cases. Fridericia's points, ac- 

 cording to Cahn, confirm the downward trend from the 1 1 th day 

 onwards. 



It will be noticed from Table 141 that in my set of figures the uric 

 acid in the embryonic body is included in the estimations. I did no 

 experiments to determine the degree of uric acid retention, but Fiske 

 & Boyden reported that, between the 5th and nth days, the uric 

 acid content of the embryonic body never exceeds 2 mgm. per cent. 

 Between the 7th and 8th days, then, when the embryo weighs about 

 a gram (wet weight), 0-02 mgm. uric acid would be contained in it, 

 although during this time 0-5 mgm. would be excreted. 



The data for the daily excretion of uric acid — a necessary step in 

 these calculations — are shown in Fig. 330. Fiske & Boyden attributed 

 significance to the irregularities in the points of their curve, but for 

 this there is no warrant. 



Table 142. Allantoic liquid [milligrams per egg). 



Fiske & Boyden Targonski 



