PATHOLOGICAL LEUCOCYTES 



1. Neutrofbil Myelocyte. 15-20/4. A mononu- 

 clear leucocyte with numerous neutrophil (e) granules. 

 The nucleus is round or indented and stains feebly. 

 Very common in myeloid leukaemia ; it is also found 

 in the blood when there is a marked leucocytosis or in 

 pronounced anaemias, e.g., of malaria (Fig. 3). 



2. Eosinophil Myelocyte. As the former but with 

 eosinophil () granulation. Found mainly in myeloid 

 leukaemia and occasionally when the blood shews well- 

 marked eosinophilia (Fig. 3). 



3. Mast Myelocyte. As the former but with 

 basophil (y) granules which stain, however, with watery 

 stains. In myeloid leukaemia. 



4. Large Lymphocyte. 15-20/4, i.e., slightly larger 

 than large mononuclears. The nucleus is very large 

 and round, stains feebly, but has one or two distinct 

 nucleoli. There is a scanty rim of protoplasm shewing 

 a fine basophil network. They are distinguished from 

 large mononuclears by the round nucleus, by the 

 nucleoli and by the narrow rim of protoplasm ; from 

 the mature or old variety of normal lymphocyte by the 

 fact that the nucleus is quite round and not oval or long 

 and eccentric, by the difference in staining, and by the 

 scanty, not broad, rim of protoplasm. Normally they 

 occur as tissue cells in lymphatic glands and in the 

 lymph follicles of the spleen. They occur in the blood 

 in lymphatic leukaemia and allied conditions (Fig. 4). 



5. Myeloblast = lymphoid marrow cells. 10-20/4. 

 The nucleus is round or oval and stains deeply (not 

 faintly as in the large mononuclear and older lympho- 

 cytes) and a dirty grey-blue with triacid (not bluish 

 green as the lymphocytes). The protoplasm is narrow 

 and deeply basophil, more so than that of the large 



