BACTERIOLOGICAL EXAMINATION 299 



Table A 



THE WHITE BLOOD-CORPUSCLES OF THE NORMAL BLOOD 



Per cent. 



I. Lymphocytes (large and small) 22-25 



II. Large mononuclear leukocytes ") 



I 2—4 



III. Transitional forms J 



IV. Polynuclear neutrophilic leukocytes 70-72 i 

 V. Eosinophilic leukocytes 2-4 



VI. Mast-cells 0.01-0.5 



The llood-plaques are recognizable in fresh blood by their lesser size 

 (1-3 (ti), their clump formation, and their slight refractive power; they stain 

 a pale blue in methylene-blue solutions, and in the triacid stain from gray 

 to grayish brown. [In most triacid preparations the blood-plates are invisible. 

 With Eomanowsky stains they are dark plum color and are easily seen. — Ed.] 



Before entering upon the physiologic and pathologic importance of individ- 

 ual cell forms we must first describe a few cell anomalies. In different patho- 

 logical conditions decided changes in the shape and size of the red blood-corpus- 

 cles are noted, and these we designate by the term poikilocijtosis (Plate, Row 

 III). The average normal size of the red blood-corpuscle is from 8-9 /x; in 

 some conditions of the blood, besides these " normocytes " there are also very 

 small forms which may be only 2 to 3 yu in size (" microcytes ") ; on the other 

 hand we may observe large forms which are frequently from 14^15 /*, in rarer 

 cases may even reach 18, 20 and 22 ju {macrocytes, megalocytes, gigantocytes) . 

 Besides the changes in size, the manifold changes in the shape of the blood- 

 corpuscles are important, and may be looked upon as an expression of seg- 

 mentation and decomposition. 



Occasionally combined with these pure morphologic changes, but quite as 

 frequently entirely independent of them, we note in the erythrocytes deviations 

 from normal conditions which are shown by a diminution of their hemoglobin 

 contents. For example, forms of various size are noted in which the central 

 depression is very markedly extended so that only a comparatively small part 

 of the disc, often only a quite narrow rim, appears to contain hemoglobin; 

 i. e., to stain in the corresponding solution (see colored Plate, Eow III). 



A diminution in the amount of hemoglobin of the individual blood-corpus- 

 cle is also occasionally shown by a generally weaker power of staining. 



Besides these slight deviations in tinctorial properties, the red blood discs 

 frequently show marked qualitative anomalies; for instance, we note very 

 frequently blood discs which do not take a pure stain with eosin or orange, 

 but a mixed one, so that in staining with the triacid stain they are more or 

 less grayish brown, in methylene-blue eosin solution from bluish red to lilac, 

 and occasionally they may appear pure blue. This behavior, which now is 

 generally designated as " polychromatophilic degeneration," may be explained 

 by the fact that foreign substances which stain with the nuclear colors have 



[1 60-72 per cent, are normal limits, in my opinion. — Ed.] 



