XII, B, 6 Boynton: Diseases in Cattle 289 



into supposedly susceptible bull 3926. The blood had no demon- 

 strable effect either physically or by blood examination upon 

 this animal during a period of two hundred twenty-six days. 



4. From the results obtained by various investigators and from 

 the results herein cited, nothing definite can be stated as to 

 whether there is an actual infectious disease caused by a pro- 

 tozoan microorganism which Theiler classifies as anaplasma or 

 whether these marginal points are merely secondary effects from 

 various conditions. 



5. There is a possibility that there is an infectious disease 

 caused by anaplasma, and that there are bodies formed in the 

 red blood cells from various other conditions which are so simi- 

 lar in appearance and staining reaction to anaplasma that they 

 cannot be differentiated at the present time. 



REFERENCES 



1. Balfour, A. Anaplasmosis in donkeys, Journ. Comp. Path. & Therap. 



(1911), 24, 44-47. 



2. DiAS, C. E., and Aragao, H. de B. Pesquizas sobre a natureza dos 



anaplasmas, Mem. Inst. Oswaldo Cruz (1914), 6, 231-249; 2 plates. 

 (See also Brazil Medico, April 22, 1913.) 



3. JowETT, W. Some observations on the subject of marginal points, Journ. 



Comp. Path. & Therap. (1911) , 24, 40-44. 



4. Porter, Annie. On anaplasma-like bodies in the blood of vertebrates, 



Ann. Trop. Med. & Parasit. (1915), 9, 561-568. 



5. Sieber, Hans. Anaplasma marginale (Theiler). Rep. Gov. Vet. Bac, 



Dept. Agr., Union of South Africa (1909-10), 104-116; 5 plates. 



6. Spreull, J. "Marginal points" or a new intracorpuscular parasite in the 



blood of cattle in South Africa, Journ. Comp. Path. & Therap. (1909), 

 22, 354-357. 



7. Theiler, A. Further investigations into anaplasmosis of South African 



cattle, First Rep. Director Vet. Research, Dept. Agr., Union of South 

 Africa (August, 1911), 7-46. 



