LXH. Differential counting of white cells and of red cells. 



1. Appliances. Microscope with one-twelfth oil immersion 

 lens; mechanical stage (not essential but convenient). 



2. Preparation. Stain as in Lesson LXI. Write the names 

 of varieties of cells, which may become familiar to the 

 eye by the study of the colored plate, and as each differ- 

 ent cell is discovered, record that fact by a check. 



j. Operation. Begin at the upper left corner of the speci 

 men and count toward the right the different cells as 

 they come into view. When the right border comes 

 into view move the specimen so that the adjoining lower 

 field is brought into range and count back again. Mark 

 the cells found under their proper heads. After the 

 observer has become familiar with the different cells he 

 can keep in mind the neutrophiles for the entire 

 trip across the field, but the others he had best mark as 

 soon as found. 



Varieties of leucocytes. (Fig. 52 a.) 

 Polymorphonucltar neutrophiles. (Neutrophiles.) 

 Myelocytes, 

 Small lymphocytes, 

 Large lymphocytes, 

 Eosinophiles, 

 Eosinophilic myeiocytes. 



Varieties of red cells. (Fig. 52 b.) 

 Normoblasts, 

 Megaloblasts, 

 Microblasts. 

 Macrocytes, 

 Microcytes, 

 Poikilocytes, 

 Polychromatiphilic cells. 



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