188 Prof. C. S. Sherringtou. On Changes in the Blood 



drop or film. They therefore seem to me to help toward distinction 

 between these kinds of leucocytes. 



The cell can ingest particles, even hoars and days after its removal 

 from the body. In oxalated blood these cells can often be seen with 

 crystals inside them as well as adherent to them. Rarely I have 

 teen them contain a chromocyte. Both crystals and chromocytes, 

 when contained in the leucocytes, lie usually in obvious vacuoles. I 

 have occasionally seen in some of these cells fresh from the circula- 

 tion some sparse small vacuoles, but they are quite uncommon in 

 blood freshly drawn. On the other hand after some hours, or better, 

 one or two days in vitro, the cell frequently becomes riddled with, 

 small vacuoles (see figs. 2 and 3, Plate 1), so as even to resemble a 

 flake of froth. The nucleus is then hard to discover in the fresh cell, 

 but on staining with basic dyes becomes at once obvious, and is 

 then found to be no longer markedly polymerous. The cell in this 

 frothed condition is still amoeboid, although not very actively, so far 

 as I have seen. On the warm stage it however travels fairly in this 

 condition. In a great number of the vacuoles fine particles can be 

 seen, and these show that the vacuoles contain fluid, for the particles 

 inside them exhibit Brownian movement. Most of the vacuoles are 

 spherical and small, some are large, as these are for the most part 

 oval in outline. In a number of the vacuoles no particles are visible. 



The granules in the normal cell never, so far as I have seen, exhibit 

 Brownian movement, but, when the cell is dead or dying, Brownian 

 movement often affects its granules in a most marked degree, the cell 

 body acquiring a shimmering appearance from the dancing of the 

 granules. This is doubtless due to lowered vitality, or perhaps 

 lethal acidification of the cell giving its protoplasm over to imbibition 

 of the aqueous surrounding. Brownian movement of the granules of 

 a leucocyte is, in my experience, one of the signs that the cell is 

 nearly dead, and I have been interested to find it present in many of 

 the cells of certain exudation fluids and pus, although invariably 

 absent from the leucocytes of normal blood and lymph. 



In these samples of pus leucocytes with spherical excentrically set 

 nuclei occur, and the nuclei have an especial tendency to smear, just 

 as in leucocytes which have slowly died in vitro (see fig. 4, Plate 1). 



By irrigation of such weakened cells with various saline solutions 

 that affect the normal leucocyte but little and leave it still actively 

 amoeboid, the cell body, and very often the nucleus as well, can be 

 burst with an explosive discharge of the cell contents, the nucleus 

 remaining as a shrunken film attached to a fragment of cell-body. 



The finely granular leucocyte forms in the dog and cat about 

 70 90 per cent, of the heemic leucocytes. The vast majority of the 

 finely granular are always, without doubt, those designated " nea- 

 trophil " by Ehrlich and his pupils ; generally, I believe all of them. 



