NORMAL HJEMATOLOGY 155 



IV. STAINING BONE-MARROW. 



Appliances. A strong vice; saw; microscope, with one-fifth to 

 one-eighth-inch objective; fresh bone containing red marrow; slides, 

 cover-glasses, with usual equipment necessary for fixing and staining 

 films. 



Technique. Place the bone in the vice and fasten it just suffi- 

 ciently to hold it for the saw. Saw off an end and then close the 

 vice on the bone and crush it enough to make the marrow leave 

 the bone. As soon as the drop of bone-marrow forms, touch a clean 

 glass slide to it and make a spread by the slide method. Make two 

 or three spreads so as to be sure to have a good one. Then fix and 

 stain as with the blood films, using either eosin and methylene or 

 the triacid stain. 



Precautions. The bone should be as fresh as possible. The 

 piece should be sawed just before using so as to have a freshly cut 

 surface from which to take the marrow. The spread is apt to be 

 too thick. Use just as much care in cleaning the slides and making 

 the spreads as when making the blood films. 



Questions. 1. Name and describe the different cells found in 

 the red bone-marrow. 



2. Are there cells found here that are not found in the normal 

 blood? 



3. What is the difference between a myelocyte and a leukocyte 

 of the same size? 



Corpuscles of Red Bone -marrow. Red Cells. Normocyte, non- 

 nucleated, 6 to 8 microns in diameter; normoblast, nucleated, 6 to 

 8 microns in diameter; microcyte, non-nucleated, 4 to 6 microns in 

 diameter; microblast, nucleated, 4 to 6 microns in diameter; megalo- 

 cyte, non-nucleated, 8 to 10 microns in diameter; megaloblast, 

 nucleated, 8 to 10 microns in diameter; poikilocyte, non-nucleated, 

 distorted. 



White Cells. Same as those in normal blood. 



MYELOCYTES. (a) Neutrophile. Irregularly spherical, 10 to 

 20 microns in diameter. It has a single or partially divided nucleus, 

 nearly filling the cell, and stained a pale blue. The protoplasm is 

 filled with neutrophile (fine) granules stained a bluish red. 



(b) Eosinophile. Same as above, except the nucleus is less 

 distinct and the protoplasm is filled with coarse granules stained 

 a bright red. 



