(Triacid Stain.) 



% 

 i, 2, 3, 4. Small Lymphocytes. 



Contrast the faintly colored protoplasm of these cells in the triple stained specimen, with 

 their intensely basic protoplasm in the film stained with eosin and methylene-blue, 17 and 18. 

 The cell body of i is invisible. Note the kidney-shaped nucleus in 4. 



5, 6. Large Lymphocytes. 



With this stain the nucleus reacts more strongly than the protoplasm; with eosin and meth- 

 ylene-blue (19, 20), on the contrary, the protoplasm is so deeply stained that the nucleus 

 appears pale by contrast. This peculiarity is also observed in the smaller forms of 

 lymphocytes. 



7, 8. Transitional Forms. 



Note the moderately basic and indented nucleus, and the almost hyaline non-granular 

 protoplasm. Compare 8 with the myelocyte, 7, Plate I, these cells differing chiefly in that 

 the myelocyte contains neutrophile granules. 



9, 10, ii. Polynuclear Neutrophiles. 



These cells are characterized by a polymorphous or polynuclear nucleus, surrounded by 

 a cell-body filled with fine neutrophile granules. In 11 the nuclear structure is obviously 

 separated into four parts; in 9 it is moderately, and in 10 markedly, polymorphous. 



12, 13. Eosinophiles. 



The nuclei are not unlike those of the polynuclear neutrophile, except that they are some- 

 what less convoluted, and poorer in chromatin, staining less intensely. The protoplasm is 

 filled with coarse eosinophile granules, the characteristics of which are clearly illustrated 

 by 13, a "fractured" eosinophile. 



14. Eosinophile Myelocyte. 

 Compare with 15. 



15, 16. Myelocytes. (Neutrophilic.) 



These cells are morphologically similar to 14, except that they contain neutrophile instead 

 of eosinophile granules. Note that the granules of the myelocyte are identical with those 

 of the polynuclear neutrophile. A dwarf form of myelocyte is represented by 16. 



(Eosin and Methylene-blue.) 



17, 18. Small Lymphocytes. 



Note the narrow rim of pseudo-granular basic protoplasm surrounding the nucleus, and 



the pale appearance of the latter. 

 19, 20. Large Lymphocytes. 



Budding of the basic zone of protoplasm is represented by 20. Both of these cells belong 



to the same type as 5 and 6. 

 21, 22. Large Mononuclear Leukocytes. 



Compared with 19 and 20, these cells have a decidedly less basic protoplasm, but a somewhat 



more basic nucleus. In the triple stained film these differences cannot be detected, so 



that they must be classed as large lymphocytes. 



23. Transitional Form. 



The distinction between this cell and 24 is not marked; the nucleus of the latter simply 

 being somewhat more basic and convoluted. 



24, 25, 26, 27. Polynuclear Neutrophiles. 



With this stain these cells show a feebly acid protoplasm, and lack granules. Note that 

 the more twisted the nucleus the deeper it is stained. Compare with 9, 10 and n. 

 28, 29. Eosinophiles. 



Compare with 12 and 13. 



30. Eosinophilic Myelocyte. 



Compare with 14. 



31. Basophile. (Finely granular.) 



This cell is characterized by the presence of exceedingly fine ^-granules, staining the pure 

 color of the basic dye. The nucleus is markedly convoluted and deficient in chromatin. 

 The cell here shown was found in normal blood. 

 3 2 33, 34, 35, 36. Mast Cells. 



The granules take a modified basic color, as shown by their royal-purple tint in this illus- 

 tration. Note their unusually large size and ovoid shape in 35, their peculiar distribution 

 in 35 and 36, and their irregularity in size in 32 and 36. With the triacid mixture these 

 granules, as well as those of the finely granular basophile, 31, remain unstained, showing 

 as dull- white stippled areas in the cell-body. The nuclear chromatin of the mast cell is so deli- 

 cate and so feebly stained that it is barely visible. These cells were found in the blood of a 

 case of splenomedullary leukemia. 



