646 EISEN. ' [Vol. XV. 



Table of Various Kinds of Blood-Plates. 

 A. Bodies with Organic Structure. 



1. True blood-plates or plasmocytes, consisting of various spheres with 

 centrosomes and refractive granules. These bodies possess an organization, 

 and the power of growth, movement, secretion, and assimilation, so far 

 found only in mammals and batrachians. 



2. Fusiform corpuscles, possessing a nucleus and cytoplasmic spheres. 

 In one species, at least, they give origin to plasmocytes. The nucleus 

 rapidly disintegrates. Found in birds, reptiles, fishes, and batrachians. 



3. Disintegrating erythrocytes, leucocytes, and other cells with no special 

 function. Probably found in the blood of all animals. 



B. Bodies without Organic Structtcre. 



4. Precipitates, chemical or mechanical, of globulin and fibrin. They 

 possess no structure, and must be considered as waste or accidental 

 products. 



VII. General Description of the Blood-Plates. 



As I have suggested above, the only elements in the human 

 blood which should be considered as true blood-plates are those 

 small disc-like bodies which possess distinct marginal filaments 

 and show a decided interior organization. 



The habit and location of the blood-plates have so frequently 

 been described that detailed reference to them is not necessary. 

 Suffice it to say that they occur singly or in groups, — from a 

 dozen or less up to several hundred, though generally number- 

 ing from few to twenty. When in groups, the individual blood- 

 plates may be packed more or less closely together, apparently 

 adhering to each other with their outer fringed edges. 



Figs. I and 2 illustrate two such groups, stained with 

 eosin-haemalum. As will be seen, the plates vary considerably 

 both in shape and size. The shape, however, is generally round, 

 or slightly oval, or even irregular, with numerous cytoplasmic 

 filaments. In Fig. i some of the blood-plates are seen to be 

 surrounded by a red-staining, homogeneous protoplasm of doubt- 

 ful nature, while in Fig. 2 very little of such protoplasm is 

 visible, most of the blood-plates being entirely free or isolated. 



