DR. DAVY ON THE TORPEDO. 



535 



Table II. 



Table III. 



The mean of the results contained in these Tables is, that the weight of the egg 

 before any appearance of the embryo is 1 82 grains ; and after its appearance, in- 



by the kidneys of the chick in ovo ; nor have I succeeded in detecting urea in the fluid it contains, a substance 

 which I have found in a notable quantity in the fluid of the uterine cavity of the Squalus Squatina, and in 

 abundance in the liquor amnii of the Dog about the fifth week of pregnancy, and have also detected in the 

 human liquor amnii at the full period. In the cloaca of very young Torpedos I have sometimes seen a trans- 

 parent fluid, probably urine, but in too small quantity for examination. The nature of the urinary secretion 

 of the advilt Torpedo I have not yet been able to ascertain ; I suspect that it is liquid, and that it is voided al- 

 most as rapidly as it is secreted, the fish being without a urinary bladder, and its cloaca of narrow dimensions. 



3z 2 



