III2 PROTEIN METABOLISM [pt. iii 



thin towards hatching, and the operation of the hatching enzyme (see 

 Section 24-2) will not be without a powerful effect. The amount of 

 nitrogen accounted for by the membrane might therefore leave some 

 20 mgm. for the urea nitrogen, which would thus be 2-3 per cent, of 

 the initial nitrogen content. But such a calculation is beset with the 

 difficulties due to our ignorance, and no great emphasis can be laid 

 upon it. 



Table 151. Gortner' s figures for Savelinus fontinalis. 



% of total nitrogen 



Gortner's data for the distribution of nitrogen are seen in Table 151. 

 As he took no trouble to prepare the pure protein of the eggs and 

 embryos, it is not easy to criticise the results, but there is an un- 



Table 152. Gortner' s figures for Savelinus fontinahs. 



% of total nitrogen 



Protein at Protein in com- 



zero hour busted fraction 



Ammonia nitrogen 7-56 1-77 



Di-amino nitrogen ... ... 28-60 9-17 



Mono-amino nitrogen ... ... 61-55 87-14 



mistakable trend from the mono-amino to the di-amino nitrogen, 

 exactly as would be the case if there was a preferential utilisation of 

 the former for combustion purposes. This appears well in Table 152 



