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DISCOVERY REPORTS 



ALLANTOIC FLUID 

 Table II. Gas and salt content of allantoic fluid {Blue whales). 



The dissolved COj is obtained by subtracting " CO3 as COg" from "Total CO2". 



* Gas found over fluid in allantois. 



The results of analyses of allantoic fluid, performed in exactly the same way as has 

 been described for urine, are shown in Table II. The allantois in Blue whales is a large 

 bag occupying the fork of the division of the umbilical chord, which bifurcates at some 

 distance from the umbilicus — about 2 m. when the foetus is half developed. The 

 urachus runs in the middle of the chord and opens direct into the allantois. The capacity 

 of the allantois increases with the growth of the foetus and contains about 50 1. of fluid 

 when the foetus is half developed. 



Slight supersaturation with nitrogen is again apparent. More attention has been paid 

 to carbon dioxide content, which is seen to be high, as in urine. Large amounts of com- 

 bined carbon dioxide were found in the twelve samples in which this was estimated. 

 The dissolved carbon dioxide, obtained as before by subtracting the combined from the 

 total carbon dioxide, shows less variation than in the urine; the range is from 13-4 to 

 337 vol. per cent, excluding no. 20, in which a large bubble of gas was seen above the 

 liquid before the allantois was punctured. The average content is 22-4 vol. per cent; 

 four samples have contents agreeing with the average to within i vol. per cent. These 

 figures for allantoic fluid are considered to represent more nearly the normal conditions 



