146 



JAMES ERNEST KINDRED. 



cells take but a passive part in the formation of a clot and none 

 at all in phagocytosis, they will not be considered further. The 

 name leucocyte which Goodrich applied to the first type of 

 amibocyte will be used here to designate the type of amibocyte 

 active in the process of phagocytosis and clotting. 



The leucocytes of Arbacia have the same general appearance 

 as those figured by Goodrich for Asterias, but the membranes 

 of the leucocytes of Arbacia seem to be larger in comparison to 

 the amount of endoplasm than do those of Asterias. As the 

 leucocyte moves about in the plasma medium the membranes 

 are constantly changing (Fig. I, a, b, c). In the living condition, 



b c 



FIG. i, a, b, c. Leucocyte of Arbacia moving freely in plasma medium, drawn 

 at five-minute intervals. Semi-diagrammatic. X 1,500. eel. pr., ectoplasmic 

 process; en., endoplasm; n., nucleus; vo., vacuoles. 



the cytoplasm of the leucocyte appears finely granulate and 

 contains five or six hyaline vacuoles. The nucleus is scarcely 

 discernible in the living cell, but when treated with Flemming's 

 or Herman's fluid it appears as a large ovoid body with a very 

 distinct membrane. The chromatin granules are very prom- 

 inent in the nucleus of those cells stained with Haidenhain's 



FIG. 2. Leucocyte of Arbacia from clot. Semi-diagrammatic. X 2,500. 

 ct., cytoplasm; n., nucleus; nc., nucleolus; pr., ectoplasmic process. 



