44 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



ments," and those mentioned above were all that it was 

 practicable to try in the time at Miss Hobbin's disposal. The 

 results are still uncertain and, no doubt, other experiments 

 will have to be made. 



Another series of experiments made by Miss Hobbins was 

 to note what changes take place in the parasite itself, and for 

 this purpose hanging drops of fluid from the kidney, containing 

 a small number of the parasites, were suspended from a cover- 

 slip. Cells of vaseline were made on the slides, and the cover- 

 slip with its hanging drop was placed on the cell. 



The preparations w~ere examined at intervals of a few 

 minutes, and notes and drawings were made daily, the position 

 of the parasite being denoted in each drawing so that any 

 change could be easily detected. To the naked eye the parasite 

 had the appearance of a rounded milky white dot. Under 

 the microscope these dots were found to show several stages. 

 Some of them appeared opaque and occasionally granular. 

 These were the trophozoites which were in preparation for 

 becoming microgametocytes. After the expiration of about 

 twenty-four hours the outlines of a large number (generally 

 about twenty) of smaller rounded masses could be seen inside 

 the microgametocyte ; they possessed a dark centre and a 

 lighter ring round the periphery, and at a still later stage they 

 were set free into the surrounding fluid. These masses were 

 afterwards discovered to be groups of microgametes. Round 

 the edge of each mass was a single layer of nuclei, which in 

 the next stage separated one from another — each taking with 

 it a small portion of the cytoplasm. Previously it had been 

 thought that the bodies, described above as microgametocytes, 

 were zygotes undergoing division preparatory to the formation 

 of spores. Other of the parasites were found to contain large 

 numbers of tiny spores with two sporozoites in each. These 

 were set free by the bursting of the sporocyst. 



A large amount of material was fixed in Bouin's fixative 

 for examination by means of sections in Liverpool. 



