466 VETERINARY BACTERIOLOGY 



in the blood. They are small, spherical, rarely more than one- 

 tenth of the diameter of the cell, frequently less. By appropriate 



.. 



Fig. 205. Anaplasma marginale in red blood-cells. Note the irregularity in 

 size and in the staining of these cells (Sieber). 



staining methods the presence of a central granule surrounded by 

 a less apparent capsule may be demonstrated. Sieber has ob- 





Fig. 206. Anaplasma marginale, stained by Heidenhain's hematoxylon : 

 a, Single parasite; 6, beginning of division, the diplococcus types; c, dumb-bell 

 forms; d, completed divisions; e, free parasites (Sieber). 



served multiplication of the organisms within the blood-cells by 

 a simple type of division. 



