300 BLOOD AND BLOOD EXAMINATION 



been deposited in the plasma of the red blood-corpuscle (see Plate, Eow II). 

 [There are many, and on the whole convincing, reasons for regarding these 

 granules as evidence of regeneration or of unripeness, but controversy is still 

 active on the subject, and it seems best for the time to use some neutral term 

 such as "basophilic stippling." — Ed.J 



Such a deposit' of substances which, for example, stain in methylene-blue 

 but not, however, in the triacid solution, is found in a granular or" dust-like , 

 form in the protoplasm of the red blood-cells, whether this is normally stained 

 or degenerated in the manner above described (polychromatophilia) (see 

 Plate, Row VI)- We should be cautious in assuming the identity of these 

 deposits with the granules of the white blood-corpuscles; therefore we should 

 also avoid the designations granular, granulation, granulated erythrocytes, 

 etc., and choose the non-implicating designation " stippled erythrocytes." 



Much less frequent than these staining anomalies of the red blood-corpus- 

 cles is an additional one, the appearance in the circulating blood of nucleated 

 red blood-corpuscles, " erythroblasts." It is well known that normally in 

 the red bone-marrow nucleated red blood-corpuscles appear. These are about 

 the. size of the normal non-nucleated blood discs, but contain a nucleus of an 

 extraordinarily intense stain and a protoplasm that usually appears in the 

 color of the stains that color hemoglobin, more rarely in that of polychromato- 

 philic degeneration. They are unquestionably the early stages of the normal . 

 erythrocytes, and for this reason are designated as normoblasts (see Plate, 

 Eow IV). On the other hand, only under pathological conditions in the 

 adult do we find another form of erythroblasts which are decidedly larger 

 than the normal red blood discs, and have a diameter of 14, 16, even 20 /* and 

 more. Their nucleus, as a rule, is but feebly stained by nuclear dyes, their 

 protoplasm almost invariably shows the condition of polychromatophilic degen- 

 eration. We designate this variety of cells as megalohlasts, or gigantoMasts 

 (see Plate V, a, b), and recognize in them the embryonic stages of megalo- 

 cytes and gigantocytes. 



In the white blood-corpuscles changes in form or in staining property are 

 of slight importance. It should be mentioned that very frequently the proto- 

 plasm of the lymphocytes at its border shows proliferation and segmentation, 

 processes which indicate a degenerative condition without our being able to 

 assign to them definite pathologic importance. 



Much more interesting is the appearance in the circulating blood of a cell' 

 form which, under normal conditions, is met with only in the bone-marrow. 

 This is a mononuclear leukocyte of varying size (8 to 20 m in diameter) (see 

 Plate, Eow XII), the protoplasm of which is filled by a dense neutrophilic 

 granulation ; Ehrlich has given this corpuscle the name " myelocyte." 



The white blood-corpuscles show variations of great importance in their 

 number, both as regards their total number per cubic millimeter and in their 

 proportion to the red blood-corpuscles (^) and particularly, in the propor- 

 tion of the individual forms of the white blood-corpuscles to one another. ' The 

 estimation of the proportion of ^ is possible by the aid of Thoma's appa- 

 ratus for counting the absolute numbers ; this may also be accomplished with 



