Host- PLANTS in- somi-: of tiik loranthack.k. t^^j 



(3 Jan.. 1895). Prof. Schonland has dealt with the " Wood- 

 flowers " on Burkca Africana, caused hy Loranthus Drcgci 

 (Records. Albany Museum. Vol. II. p. 435), and in the same 

 work records several host plants. 



The main object with which T set out to note the ditierent 

 host plants was to supplement the records in the local herbarium 

 and that given for this locality in the " Flora Capensis," but T 

 hope in time to extend the observati' ns so as to embrace other 

 interesting points connected with these plants. 



THE LENGTH OF TIME WHICH PIROPLASMA 

 BIGEMINUM AND ANAPLASMA CENTRALE SUR- 

 VIVE IN CITRATED BLOOD. 



By E. M. Robinson, M.R.C.V.S., 

 Veterinary Research Labora>tor\, Ondcrsiepoort. 



Read July 10. 1919. 



The experiments described in this paper were undertaken 

 with the object of determining how long Piro plasma bigemiiium 

 and Ana plasma cent rale remained alive and capable of reproduc- 

 ing redwater and anaplasmosis, when the blood containing them 

 was preserved with sodium citrate solution for varying periods 

 of time. During the past five years blood from imported cattle 

 inoculated with a mild strain of redwater and a strain of Ana- 

 plasma Centrale, the mild form of anaplasmosis. has been used 

 to immunize cattle against these two diseases in South Africa. 

 The blood of these imported cattle was citrated, 90 parts of blood 

 being added to 10 parts of 10 per cent, solution of sodium citrate 

 in distilled water, and sent out to various cattle owners, the dose 

 prescribed being 5 c.c. to be inoculated subcutaneously. A warn- 

 ing was given to the cattle owner that the blood should be used 

 not later than five days from the date of issue from this labora- 

 tory. This time-limit was quite arbitrary, as no experiments had 

 been done, at the time the vaccine was first issued, to determine 

 the resistance of the parasites in citrated blood. During the 

 early part of 1918, reports were received from various sources 

 that the vaccine did not seem to ])rodnce redwater reactions, and 

 as some of the stock-owners who made these reports were good 

 observers, it was decided to make a few experiments in this con- 

 nection. The number of available susceptible cattle was very 

 limited at the time. April, 1918, but none of the cattle used had 

 been exposed to either redwater or anaplasmosis infection pre- 

 viously. 



