HISTOLOGY. 53 



2. Collect it in the same way that you did the blood 

 of man. 



3. Examine the shape of the corpuscles ; search for 

 a nucleus in the red corpuscles; measure the cells in 

 both diameters, and examine the white corpuscles for 

 the amoeboid movement. 



Exercise No. 35. Make a spread of human blood and 



apply the reagents given you, viz.: salt solution, 



acetic acid, and water. 



Irrigate in the usual way. In the salt preparation 

 r - 1 e what you see ; give the cause. Do the same with 

 all the others. Do red cells have a cell-wall? (Leroy 

 and Sobotta say they do>. 



The colorless corpuscles are of five varieties: [mono- 

 nuclear lymphocytes, poly nuclear lymphocytes, large 

 lymphocytes, eosinophiles and basophiles. These are 

 all larger than the red blood cells. They all originate 

 from the lymph glands. They are separated into their 

 classes by the use of different stains, and the use of the 

 eye-piece micrometer. A large per cent of them has 

 the power oi moving like the ameba; hence the term 

 ameboid movement, as applied to the white blood cells. 

 Blood shadows are red blood cells that have been sub- 

 jected to the action of water, and have the haemoglo- 

 bin dissolved out, leaving the shadow of the cell. Blood 

 platelets are small red cells. The crystals found in 



