262 Dr. Prevost and M. Dumas on [Oct. 



Common Eel. Mr. Hewson has stated the globules of the eel 

 to be circular, but they were found to be elliptical. The blood 

 was obtained from the aort?.. 



Serum. 



Water 900 



Albumen and salts , . , , 100 



1000 



Blood. 



Water 8460 



Particles 600 



Albumen and salts . , . 940 



10000 



MM. Prevost and Dumas observe, that the inspection of these 

 results will prove that it is impossible to draw any general con- 

 clusions from them respecting the composition of the serum : 

 this fluid varies in the same animal, and still more in different 

 animals, without the possibility of connecting this character 

 with the physiological condition of the individual. With the 

 particles, the case is different, and, in the greater number of 

 cases, their quantity bears a certain relation to that of the heat 

 developed by vital action, as will appear by the annexed table : 

 it shows the number of particles in 10000 parts of the blood, the 

 usual temperature of the rectum, the number of beats of the heart, 

 and the inspirations in a minute. To complete our knowledge 

 on this subject, we want the relative weights of the animal and 

 the blood in circulation. With this difficult subject the authors 

 are now engaged. 



In attempting a comparative examination of arterial and 

 venous blood, unexpected difficulties and irregular results 

 occurred. It was at length discovered that when a small animal 

 is bled to a considerable extent, the veins rapidly absorb, at the 

 expense of the rest of the system, a proportional, or perhaps an 

 equal quantity of fluid to that in circulation : from which it 



