The Structure and Functions of the ha^molymph Ghmds and Spleen. 37 



in certain g-lands, especially those richly supplied with lymph, to a far 

 larger extent than is at present suspected, as the process is much more 

 difficult to detect than erythrocyte disinteg-ration. The process of 

 breaking do"\^Ti the leucocyte seems to consist essentially in its solution; 

 the nucleus may be split up, or a giant cell may be found containing 

 irregular bodies, staining a light blue tint, which are in all probabi- 

 lity the remains of leucocyte nuclei. 



For some time there was difficulty in finding a phagocyte con- 

 taining no red corpuscles or pigment; in other words a young giant cell. 

 In many sections, however there are to be seen large clear "hyaline^^ 

 cells, the protoplasm of which stains a light blue or violet with 

 hiemalum (pi. I. fig. 11 a and pi. I. fig. 9 l.h.c), these cells are 

 usually of the same size as a phagocyte and occasionally contain blood 

 cells enclosed in vacuoles (pi. I. fig. 11 c). Mitosis is also frequently 

 seen going on in them (pi. I. fig. 11 h). The difference between such 

 a cell and one of those filled with pigment and blood corpuscles is so 

 striking that they are easily mistaken for different varieties of cells: 

 it seems very probable that they are phagocytes, either newly deve- 

 loped or in an inactive condition. 



2. Glands in ivMch Phagocytosis occurs. 



Up to the present time, the extent to which phagocytes, or giant 

 cells capable of destroying erythrocytes, are distributed throughout the 

 haemolymph organs of vertebrates has not been fully realised. They 

 have been described in the spleen by Kölliker, as already noted; in 

 the hoemal glands of the rat by Vincent and Harrison; in certain 

 lymph glands in monkeys by Schumacher; and in the haemal lymphatic 

 glands of dogs by Drummond. I have not failed to find signs of 

 l)hagocytosis jjroceeding in the hcemal or hœmal lymphatic glands of 

 any Mammal examined. In the glands of man, monkey, ox, sheep 



^) In fresh preparations Schumacher has failed to observe actual phago- 

 cytosis proceeding, though he has noticed slow amœboid movements of the giant 

 cells. I have several times watched phagocytes on the warm stage, but have 

 never seen the ingestion of red cells. I have also placed amœbas in a highly 

 dilute saline solution containing erythrocytes but never observed even the ingestion 

 of the blood corpuscles by the amœbas. 



