i. 3 6 VER Y MINUTE PAR TICLES 



surface, and sometimes these extend for some distance 

 in the substance of the surrounding tissue, and they 

 increase in number. 



" I venture, then, to conclude that many of the clear 

 fluids which have been considered as 'exudations' 

 from the blood, really contain a multitude of extremely 

 minute particles of living matter, which are intimately 

 related to the white blood-corpuscles, and that these 

 grow and become one source of the small granular 

 cells or corpuscles which are so familiar to all who 

 have studied morbid changes in the tissues as they 

 occur in man and the higher animals. 



" Some of these active living particles may be so 

 small as to be invisible by a power magnifying 5,000 

 diameters. I have seen such particles, less than the 

 50,000 of an inch in diameter, and have no reason 

 whatever for assuming that these are really the 

 smallest that exist." 



These minute particles of bioplasm multiply freely, 

 but they may also be derived from the white blood- 

 corpuscles, and from other forms of bioplasm. The 

 general appearance of such minute particles is repre- 

 sented in a minute portion of recently drawn blood in 

 Fig. 55, plate XVI. As the blood coagulates they 

 undergo change, die, and help to form the non-living 

 fibrin. In every clot numerous white blood-corpuscles, 

 also composed of living matter, can be detected, 

 Fig. 57- I* 1 coagulation it is probable that the most 

 minute particles of bioplasm change first, and become 



