Scientific Proceedings. ( io 9) 45 



ber stoppers and allowed to stand five or ten days so that contamin- 

 ations with bacteria might be detected. 



1. The blood of frogs infected with Trypanosoma rotatorium, 

 collected in the same manner, was mixed with that in blood-agar 

 tubes prepared and tested as just mentioned. The tubes were 

 kept at the temperature of the room. Cultures made from two 

 infected frogs showed, after two weeks, growths of flagellate pro- 

 tozoa (both on toad's blood-agar and frog's blood-agar). The 

 organisms were of a very long oval form, the bodies of the largest 

 being 2 11 x 18//. There was a single flagellum, which was often 

 nearly as long as the body. Only the largest forms showed a 

 trace of an undulating membrane, which never approached the de- 

 velopment of this structure in Trypanosoma rotatorium, and which 

 did not appear in stained preparations. Motility was not very pro- 

 nounced. Numerous small forms were seen evidently represent- 

 ing various developmental stages. In preparations stained accord- 

 ing to Romanowsky, a blepharoplast (micronucleus, centrosome) 

 was seen at the base of the flagellum and near the anterior end. 

 The nucleus appeared to be represented by numerous chromatin 

 granules in the posterior end. It may be noted that Smedly 1 

 found the centrosome at the anterior end in the cultural forms of 

 the rat trypanosome. Numerous observers have seen typanosomes 

 lacking the undulating membrane under artificial conditions. 



The growth in the tubes was never luxuriant. Arrangement 

 in rosettes was not seen. One generation only of subcultures 

 grew. All the cultures soon died. A single attempt to inoculate 

 a normal frog gave a negative result. These experiments were 

 interrupted, as both the authors went out of town. 



2. As is mentioned below, the blood of frogs infected with 

 Drepanidium was added to blood-agar 2 tubes to see if Drep- 

 anidium could be made to live or undergo further development. 

 Tubes thus inoculated, showed, in one case, trypanosomes in about 

 ten days. For the moment it appeared as though trypanosomes 

 had developed from Drepanidium. Some of the same blood-agar 

 to which no Drepanidium blood had been added, was examined 

 again and found to contain the same trypanosomes. They must, 



^medley: Journal of Hygiene, January, 1 905. 

 2 Made from frog blood. 



