Feeding Blood Corpuscles. 61 



beautiful intra-nuclear and in tra- cellular network of 

 fine fibres in the red corpuscles. 



FEEDING BLOOD COKPUSCLES. 



Eub up vermilion cake in f per cent, salt solution, 

 add a very small drop of this to the blood on a slide, 

 cover and examine on the warm stage, paint a little 

 oil round the edges to prevent evaporation. 



In the case of newt's blood the thermometer should 

 not rise above 30 C., and in that of human, not above 

 40 C. After a time the white blood corpuscles will be 

 found to have enclosed some of the vermilion granules. 

 Newt's blood from the larger size of the corpuscles will 

 show this best. 



IRRIGATING BLOOD CORPUSCLES. 



Make a f per cent, saline solution of newt's blood on 

 a slide, cover and examine : notice the red corpuscles 

 gradually becoming crenated. Try the effect of irriga- 

 tion on this preparation, place a small piece of filter 

 paper in contact with the edge of the cover glass, and 

 with a capillary tube place a small quantity of the fluid 

 to be introduced on the opposite side ; as the filter 

 paper withdraws fluid from one side, the new fluid will 

 flow in from the other. When thicker fluids, such as 

 glycerine are to be removed, a capillary tube is neces- 

 sary on one side to remove it by suction with the mouth. 



The fluids to be tried by irrigation are : Dilute 

 acetic acid ; distilled water ; 2 per cent, solution Tannic 

 acid; 2 per cent, solution Boracic acid. For their 

 effect the student is referred to the Atlas of Histology 

 by Dr. Klein. 



