402 



I\nCRO-ORGANIS:\IS AND DISEASE [chap. 



first with rubin and then with methyl blue, many of the 

 epithelial ceils in the region of the vesicle contain each an 

 oval or spherical homogeneous body, which by its pink colour 

 is well marked off both from the cell protoplasm and the 

 swollen and hydropic cell nucleus, both these being stained 

 blue ; but it is extremely difficult— and it seems premature 

 and improbable— to identify them as of the nature of 

 extraneous parasites, viz., coccidia : on the contrary, these 

 bodies look extremely like derivatives of the cell nucleus. 



Fig. i6i. — From a similar Specimen. 



y. 2000. 



In 1892 Guarneri describes after inoculation of the cornea 

 of rabbits with "^'ariola and vaccinia in the epithelial cells of 

 the cornea a peculiar parasite, called by him Citoryctes. L. 

 Pfeiffer, J. Clarke, and Sicherer confirmed their occurrence 

 in the corneal epithelium under the same conditions. 



Quite recently Ernst Pfeiffer {Ceiitraiblait f. Bakt. uiid 

 Parasitcnk. xviii., No. 25) describes the same bodies: 



