366 GENERATION. 



Composition of the A.mniotic Fluid. 1 



Water 991-00 to 975-00 



Albumen and mucosine 0'82 " 10'77 



Urea 2'00 " 3'50 



Creatine and creatinine (Scherer, Kobin and Verdeil) . not estimated 



Lactate of soda ( Vogt, Eegnauld) a trace 



Fatty matters (Rees, Mack) 0'13 to T25 



Glucose (Cl. Bernard) not estimated 



Chloride of sodium and chloride of potassium 2'40 to 5*95 



Chloride of calcium a trace 



Carbonate of soda a trace 



Sulphate of soda a trace 



Sulphate of potassa (Rees) a trace 



Calcareous and magnesian phosphates and sulphates . 1'14 to T72 



The presence of certain of the urinary constituents in the 

 amniotic fluid has led to the view that the urine of the foetus 

 is discharged, in greater or less quantity, into the amniotic 

 cavity. Bernard, who is quoted in the above table as having 

 determined the presence of sugar in the amniotic fluid, has 

 shown that, in animals with a multiple placenta, the amnion 

 has a glycogenic function during the early part of intra-uter- 

 ine existence. 2 



"With regard to the origin of the amniotic fluid, it is impos- 

 sible to say how much of it is derived from the general surface 

 of the foetus, how much from the urine, and how much from 

 the amnion itself, by transudation from the vascular struct- 

 ures beneath this membrane. The quantity is apparently too 

 great, especially in the early months, to be derived entirely 

 from the urine of the foetus, and there is probably an exuda- 

 tion from the general surface of the foetus and from the mem- 

 branes. After the third month, the sebaceous secretion from 

 the skin of the foetus prevents the absorption of any of the 

 liquid. 



An important property of the amniotic fluid is that of 

 resisting putrefaction and of preserving dead tissues. It is 



1 ROBIN, Lemons sur les humeurs, Paris, 1867, p. 782. 



2 See vol. iii., Secretion, p. 322. 



