f I' 



The Leucocytes in Anccmias. 163 



To a certain extent the increase of this or that particular form 

 of leucocyte is of diag-nostic importance. In brief we reco.^nize 

 as the most common form of white blood corpuscle the i)olymor- 

 phonuclear neutrophile cells (containing multiple nuclei or a single 

 polymorphous nucleus, and having numerous fine granules in the 

 cytoplasm wdiich elect a combination of the acid and alkaline dyes 

 in staining with such mixtures, becoming purplish with methylene 

 blue and eosin for example). An increase of these elements, 

 spoken of simply as leucocyfosis or hyperleucocytosis according to 

 its grade, is commonly m.et in a number of infections, particularly 

 those of the septic group. There are normally present in the 

 blood a few similar leucocytes which have, however, in their 

 cytoplasm rather coarse granules which, from an acid and basic 

 combination of dyes, select the former, being therefore called 

 oxvphile cells (or because eosin is the acid part of the common 

 methylene blue and eosin solutions and their cell granules appro- 

 priate the red of the eosin. these cells are often called eosinophile 

 cells). These oxyphile cells may become increased in a number 

 'of conditions, but this increase, know^n as eosiiiophilia, is especially 

 notable in the blood of animals or human beings subject to some 

 of the animal parasites as the trichina or hookworm. Tn pseu- 

 doleukremia and lymphatic leukaemia the lymphocytes, cells with 

 single large, deeply basic staining nuclei and with fine basophilic 

 granules in the scanty cytoplasm, are especially increased. Tn the 

 common lieno-medullary leukaemia there is special increase in a 

 large type of leucocyte not normally present in the blood but 

 natural to the bone-marrow", known as a myelocyte, with large 

 nucleus taking the basic stain faintly and with fine neutrophilic 

 granules in the cytoplasm.] 



Where there is such an increase of leucocytes in the blood that 

 thev equal or exceed the number of erythrocytes in the drop from 

 which the cell count is made, or if certain cells normally present 

 in but meager numbers are unusually numerous [the mononuclear 

 cells above noted as myelocytes] the name leiikcvmia is employed 

 to denote the condition. [The actual number has been known 

 to equal that of the erythrocytes, but this is exceptional ; and the 

 present conception of leukaemia concerns rather the type of cell 

 present in the blood, the myelocyte, than the actual numbers at- 

 tained.] In this disease the blood is apt to be changed in its 

 macroscopic appearance as well, becoming of a light red or rasp- 

 berry color. There also occur hyperplastic changes in the various 



