•2424 Journal of Applied Microscopy 



elements of the blood except the granules of the mast cells and the blood plates. 

 But slight fixation is required and dry heat (II, B, 1) is preferable, because it 

 better preserves the granules of the leucocytes. 



2. For Staining the Red Corpuscles. — The hemoglobin of the mature red cor- 

 puscle is yellow in color and acidophile in reaction, and is stained by the most 

 acid dyes (III, B,). Preparations should be well fixed by dry heat (II, B, 1). 



Lowit, for the differentiation of hemoglobin, fixed preparations in alcohol and 

 stained them 10 to 60 seconds in an alcoholic solution of aurentia, washed in 

 alcohol, cleared and mounted. 



3. For Studying the Development of Red Corpuscles. — ^Make dry preparations 

 from the red bone marrow by the method of Smith (I, 2,), fix the preparations 

 in alcohol and ether (II, B, 2, b), and stain with methylen blue (III, A, 4). The 

 cytoplasm of the immature red corpuscles is stained blue with methylen blue 

 with an intensity inversely proportional to the degree of hemoglobin develop- 

 ment. The nuclei of the nucleated forms are stained a deeper blue than the 

 cytoplasm. 



Aurentia and methylen blue (III, C, 1, b), was used by Bizzozero (1890) for 

 recognizing hemoglobin in the early development of red corpuscles in birds. 



4. For Demonstrating the So=Called Degenerative Changes in Red Corpuscles. — 

 These changes include the polychromatophile corpuscles, the basophile granula- 

 tions of red corpuscles and megaloblasts. They are mostly regenerative in nature 

 and basophile in reaction. Loffler's alkaline methylen blue, either alone (III, 

 A, 4, b), or counter-stained with eosin, is the simplest and best staining for this 

 purpose. The neutral eosin-methylen blue stains also show these forms. 



Caste/lino (1892) used aurentia and methylen blue (III, C, 1, c) for studying 

 the degenerative changes in red corpuscles. 



5. For Staining Lymphocytes. — Both nuclei and cytoplasm of lymphocytes 

 are basophile, the nuclei strongly and the cytoplasm more feebly basophile. 

 Fixation in alcohol and ether (II, B, 2, b) and staining with Loffler's alkaline 

 methylen blue (III, A, 4, b) is best for this purpose. 



Ehrlich recommends double basic staining with methyl green and fuchsin 

 (III, A, 6) for demonstrating lymphatic leukaemia. 



6. For Differentiating the Granuliferous Leucocytes. — The eosin-methylen blue 

 neutral stains (III, D, 5) stain differentially the basophile, acidophile and neu- 

 trophil granules of the leucocytes, both of the normal polymorphonuclear 

 forms and of the mononuclear forms (myelocytes) that appear in the circulating 

 blood in disease. 



Ehrlich's tricolor neutral stain and its modifications (III, D, 4), his neutral 

 fuchsin-methylen blue stain (III, D, 1) and Rosenberger's phloxin-methylen blue 

 stain (III, D, 2) differentiate the acidophile and neutrophile granules. The 

 acidophile granules are also stained by most acid dyes (III, B). 



The basophile granules of the mast cells are stained by the neutral eosin- 

 methylen blue stains (III, D, 5) and by the dahlia solution of Ehrlich (III, A, 1, a), 

 Westphal (III, A, 2) and Goldhorn (III, A, 1, b). 



7. For Studying the Development of the Leucocytes. — Make dry preparations 



