40 CALIFORNIA ACADEMY OF SCIENCES. [3D Ser., 



distance than under ordinary conditions, then becoming 

 suddenly paralyzed and unable to again contract. In fig. 

 76 I have figured such a plasmocyte. It was at first only 

 oblong rounded, with short plasmospheric projections. In 

 a couple of minutes these had reached their present size. 



In ordinary plasmocytoblasts and plasmocytes there is 

 much variation in the appearance of the outer edge of 

 the plasmospheres. In some plasmocytes the rays are 

 pointed and very long, in others again they are rounded 

 and scarcely projecting. While the former rays may be 

 explained as being fragments torn from the cell mem- 

 brane of the erythrocyte, the rounded appearance of the 

 latter can only be considered as a direct effect of amoeboid 

 contraction. Another sign of amoeboid movement is the 

 presence of bacteria, foreign bodies of various kinds and 

 size, as well as fragmentary or even whole red blood cells 

 lodged in the granosphere of the plasmocyte. Their pres- 

 ence can only be explained by amoeboid movements of the 

 plasmocyte, the latter having engulfed them in the same way 

 as do leucocytes and other wandering cells. 



As regards each one of the inner spheres, separately, it 

 is evident that the peculiar forms frequently possessed by 

 them must be attributed to amoeboid movements. Such 

 undoubted activity is especially seen in the centrosphere, 

 and to a lesser extent in the granosphere and somosphere. 

 In each one of these spheres we can recognize a rest- 

 ing stage and a stage of amceboid activity. While the 

 resting form of each of these spheres must be con- 

 sidered as approaching a disk, other forms frequently 

 occur which cannot be the effect of accidental pressure or 

 disturbance. As a plasmocyte with a resting archosome, 

 I consider, for instance, the one shown in fig. 47, where 

 both the centrosphere and the somosphere are oval. Figs. 

 27, 48, 49, 68, 69, 82, and others, show the various spheres of 

 the microcentrum as arrested in the amoeboid stage. That 

 this amoeboid stage is not confined to the plasmocyte as a 

 whole is evident from such figures as 23, 32$, 35a and 82, 

 all of which show signs of a most active movement of the 



