STUDY OF PATHOGENIC AMCEBiE FROM BOMBAY. 109 
engaged in the study of dysentery in India, for the cultures I 
have used. 'These cultures of amoebae I understand were 
obtained in Bombay from the following sources : (a) a liver- 
abscess ; (b) a dysenteric stool ; (c) Bombay City tap-water ; 
(d) the stool of a healthy monkey. 
A period of leave to England presented me with a favour- 
able opportunity for studying these cultures under the control 
and guidance of a skilled protozoologist. I have to thank 
Dr. Martin, the Director of the Lister Institute, and Professor 
Minchin, of the London University, for allowing me to work 
in the laboratory at the Lister Institute, and the latter 
especially for drawing up for me a scheme of research in 
connection with the cultures I had obtained, and for instructing 
me in the best methods for studying the amoebae. 
Professor Minchin suggested that I should endeavour to 
ascertain whether the amoebae from these different sources 
were one and the same species, by studying their morphology 
and development in cultures, and, by using the physiological 
test, attempt to produce dysenteric lesions in animals. He 
further suggested that I might find out whether these parasitic 
amoebae absorb food osmotically, like a trypanosome, or must 
devour things like the ordinary free-living amoebae. I was to 
endeavour, if possible, to get pure cultures free from bacteria. 
A preliminary examination of the cultures, which had been 
planted more than a month previously, showed that in each 
case all the amoebae were encysted, and that in all they were 
associated with a variety of bacteria. The size of the cysts 
in the different cultures varied considerably, but it was 
observed that on the whole the Cysts in the culture obtained 
from a dysentery-stool were smaller than those found in the 
cultures obtained from Bombay tap-water and from the 
monkey. The cysts in the liver-abscess culture varied more 
considerably than the other cultures; many very small cysts, 
often grouped together, were mixed with cysts as large as 
those found in the water or the monkey culture. It appeared, 
then, that in the case of the liver-abscess culture two types 
of cysts were present. Measurements of the cysts showed 
