consequent upon Inflammations of acute local Character. 193 



should estimate the ordinary frequence as between 10 per cent, and 

 1'2 per cent, of all hsemic leucocytes. 



G. The Hyaline Leucocytes. 



This class is probably a less homogeneous collection than either of 

 the other two. Two subdivisions of it are important. I. Small cells, 

 lymphocytes. II. Larger cells, myelocytes. One however often 

 meets with individuals in whose case one feels hesitation before de- 

 ciding as to which of the two subdivisions they shall be assigned. 



I. Small Cells. These are, for the most part, M. Schultze's 

 "smallest" cells; the nucleus is spherical, and stains deeply; the 

 cell body is small, sometimes a mere film coating the nucleus. The 

 cell body is apt to stain deeply with methyl blue and other basic dyes. 

 I agree with Schultze that this cell is not amoeboid in the blood. It 

 also seems less sticky than the other leucocytes. In the counting 

 solution the nucleus of this cell is the first living structure to become 

 tinged with colour. When platelets (precipitate) are present these 

 tinge even earlier, but of a violet colour, whereas the nucleus of the 

 small hyaline cell takes at first a pure light blue ; and there is no 

 evidence that the platelets are living structures. 



II. Larger Cells. Some are among the largest of hsemic leuco- 

 cytes. The cell body encloses a spheroid, ovoid, or reniform nucleus, 

 the chromatin of which is patchily distributed, and not so condensed 

 as in the partinucleate leucocytes. The cell body tinges in many 

 individuals deeply and evenly with basic dyes, but in other indi- 

 viduals, as Everard, Demoor, and Massart* have especially pointed 

 out, hardly at all. This cell is, in my experience, sluggishly amoeboid. 

 It is, however, phagocytic. 



I have very frequently noted that in specimens in which the large 

 hyaline leucocyte is numerous the small hyaline is also more numerous 

 than in specimens in which the large hyaline cell is scanty. The two 

 varieties seem to vary in the same direction. The number of hyaline 

 leucocytes varies greatly in normal blood ; I estimate it to average 

 (in dog and cat) at between 5, 7, and 20 per cent, of the total leuco- 

 cytes. When their number is large the blood is usually of low 

 specific gravity, of low haemoglobin value, and contains a relatively 

 poor number of chromocytes, i.e., the blood is polyplasmic. 



The hyaline leucocytes probably correspond pretty closely with 

 Lowit'sf " mononuclear " class. 



All haamic leucocytes appear to me to be to a large extent anaerobic 

 organisms. The amoeboid varieties, for instance, continue amoeboid 



" Sur les Modifications des Leucocytes dans 1'Infection et dans I'lmmunisation," 

 ' Annales de 1'Institut Pasteur,' p. 165, February, 1893. 

 t Op. tit. 



