REPORT 0V DOURINK. 61 



marked vacuoles or halos at and around the sqat of the micro- 

 nucleus both before and after division. Indivi lual rns 

 <';ich with single micro and macro-nucleus exhibited a num!>cr of 

 red granules within the body cavity. In addition the protoplasm 

 of protozoa underpin* division, in the early, intermediate and 

 final stages, just before separation, also contain granule'. 



6th day. Slight decrease in number of the mature organisms, 

 while the developmental forms remained stationary with regard to 

 numbers. 



7th day. Great decrease in the numbers of the mature forms, 

 and corresponding increase in the amoeboid and plasmodial. 



8th day. Out of fifty-four forms only two mature trypano- 

 somata observed, one a young protozoon and the second undergoing 

 longitudinal division. 



9th day. No trypanosoma present, only amoaboid and plas- 

 modial forms discovered. 



10th day. No more mature forms. 



In the blood of horses suffering from Surra, the trypanosomata 

 frequently exhibit large numbers of granules, which are especially 

 observable during the height of a Surra paroxysm, i.e., when the 

 haematozoa are swarming, but they may be seen in still larger 

 numbers when the protozoa have been swarming in the blood for 

 several days just previous to the death of the host, In 1891, I 

 observed the organism shoot forth a large number of these bright 

 refractile particles into the blood plasma; but although searched 

 for, the same phenomenon has not been noted in the case of the 

 Dourine parasite ; nevertheless the game changes would no doubt 

 be seen to take place if the exact moment could be hit off and be 

 made use of in advancing the purpose of this particular observ- 

 ation. 



VII. In what form do trypanosomata leave plagues and again 

 enter the general circulation. 1 ' In plaques which persist for a 

 number of days, certain changes take place as before noted which 

 only allow of the developmental forms of the Dourine trypanosoma 

 returning to the general circulation, but in those plaques which only 

 persist for a few, up to a maximum of 48 hourg, the changes noted 

 above have not time to take place, consequently the mature 



