CHAP. IX.] 



THE CONTRACTILE TISSUES. 



397 



OBSERVATIONS OF DR. PAVY. 



Before these figures can be compared it is necessary to remark that 

 the tables do not include the nitrogen eliminated in the faeces, or that 

 eliminated in the urine otherwise than as urea and uric acid. Compared 

 with the nitrogen of the urea and uric acid, the nitrogen of the other 

 egesta named is indeed small and unimportant; still inasmuch as the 

 nitrogen eliminated as urea and uric acid does not bear a constant relation- 

 ship to that otherwise excreted, no comparison is perfect which does 

 not include the latter. Unfortunately the experiments of Flint and 

 Pavy do not, together, furnish us with the necessary data for a perfect 

 comparison. 



