422 SCIENCE PROGRESS. 



to be nutritive material accumulated within the cell, or to 

 be substance elaborated by the protoplasm in virtue of 

 secretory activity. Ranvier (17) takes the former view, 

 Ehrlich the latter. Kanthack and Hardy (2) have shown 

 that by bringing into the proximity of the cell certain 

 bacteria a condition of extreme activity can be produced 

 in it, and that under this excitation the body of the cell 

 rapidly becomes clear of its granules. The granules are 

 after a while reformed, but the new ones are at first not 

 quite like those previously present. This observation of 

 the lysis of the granules is fraught with great interest, 

 because the same observers have shown that the cell is 

 able to greatly damage the bacteria offered to it, and this it 

 must effect by means of its secretion. The cell may there- 

 fore be looked upon as a free unicellular gland. 



A further peculiarity of the cell is that though it is very 

 vigorously amoeboid, and can throw out remarkably active 

 pseudopodia, it is incapable of incepting particles, and 

 vacuoles are never seen within it. By adding to fluids 

 containing these and other leucocytes particles suitable for 

 recognition, e.g., pigment, bacteria, crystals, etc., the large 

 hyaline and the finely granular oxyphil cells take these up 

 speedily, imprison them in vacuoles, and, in the case of 

 proteid particles and bacteria, in many instances digest 

 them ; but the coarsely granular oxyphil cells, although 

 they may affect contact with the particles, have never 

 under any circumstances been seen to incept any. This, 

 presumably, is the reason why in the blood of malarial 

 patients the hyaline and finely granular leucocytes are pig- 

 mented, but the coarsely granular never exhibit pigmentation. 

 The formation of vacuoles in the coarsely granular oxyphil 

 leucocyte, if it occurs at all, is an event of great rarity. 



The habitat of the coarsely granular oxyphil leucocyte 

 includes the blood, the lymph, serous fluids, and the clefts 

 of the connective tissues, except cornea and tendon. They 

 are relatively to other leucocytes more numerous in the 

 peritoneal fluid than in the blood or lymph ; in the blood of 

 the cat they constitute from 2 per cent, to 8 per cent, of all 

 the leucocytes. Abstinence from food, if not very pro- 



