PIROPLASMA AND TRYPANOSOMA OF CATTLE. 157 



blood cells could be recognized by the irregular form, which they assumed 

 and by the marked metachromasia present. The piroplasmata assumed 

 a rounder shape and became collected in larger groups. A number of 

 them showed the characteristic rays first described by Kobert Koch, 

 which are probably composed of protoplasm, since with the Eomonowsky- 

 Giemsa stain they acquire the same blue color as the remaining proto- 

 plasm. These ray forms appeared to be especially distinct on the second 

 or third day of cultivation. The piroplasmata in the culture became 

 larger and showed as a rule only two chromatin masses in the blue ground 

 of their protoplasm. Later the forms of Koch with chromatin jjoints 

 appear; usually they are found on the third day for the first time. 



These forms recall those resembling an arrow point which were found 

 within the red blood cells of the "original calf." There is a temptation 

 to assume a relationship between them. (See Plate I, fig. 4, a, and Plate 

 II, fig. 2, d, and Plate VI, fig. 32.) 



Beside these forms there were still others observed in the cultures 

 which Avere of about the size of a red blood cell and which contained from 

 two to three bright red chromatin masses and several (2 to 4) dark brown 

 red cliromatin granules. Their form was in general oval ; many of them 

 showed rays which stained the same briglit blue color as the remaining 

 protoplasm. These large forms were found scattered among the smaller 

 ray forms and occasionally were situated apart from them. The signifi- 

 cance of these forms is not clear. In morphology they conform so closely 

 to those observed outside the red blood cells which were found in the 

 fresh blood of the "original calf," that one must tliink of a relationship 

 between the two (see Plate II, fig. 2, e, and Plate VI, figs. 33 and 34; 

 and Plate I, fig. 5, c, and Plate III, fig. 8.) 



One might be inclined to regard them as macrogametes ; yet there is 

 need of further proof before such an opinion is justified. Also the idea 

 that the forms with chromatin points which appear at the same time 

 are microgametes requires confirmation. Further stages of develop- 

 ment have not been observed. All these forms described above apparently 

 died after from five to about eight days in the culture media kept at a 

 temperature of 28° to 29° C. 



This experiment showed — 



1. The presence of a variety of Texas fever organism in the blood of 

 calf No. 5 as in that of calves Nos. 1 and 2. 



2. The failure to transfer trypanosomata by means of the inoculation 

 of the fresh blood of the "original calf," as was the case with calf No. 2. 



Calf No. 5 {repetition of the experiment performed on calves Nos. 1 and 3). — 

 Marcli 4, 1909; new-born male calf from Indo-Cliina; free from ticks; fed witli 

 preserved milk; blood smears show no parasites; blood culture negative. A 

 monkey received 15 cubic centimeters of its blood subcutaneously and remained 

 liealthy and free from parasites. 



