R. T. Wells 
207 
them out as dysentery amoebae, whereas these cultivated forms have 
absolutely nothing to do with genuine parasitic amoebae but belong to 
the Limax group.” 
Doflein (1909), after considering the various amoeboid organisms 
which have been described as occurring in the faeces, dwells upon the 
diflficulty of coming to any clear idea as to which of the following 
headings such organisms should come under: (i) “gelegentliche Pas- 
santen des Darms,” i.e. casual visitors in the gut or pseudoparasites; 
this group includes saprophytic amoebae swallowed in the encysted 
condition and excreted unchanged, (ii) facultative parasites, (iii) amoebae 
specifically adapted to the parasitic habit. 
Recently, Whitmore (1911) has examined two cultures, on Musgrave’s 
medium, of amoebae originating in Manilla, one from faeces, the other 
from liver abscess pus. He came to the conclusion that the amoebae 
fi'om these different sources showed some differences among themselves 
but that both belonged to the “ Limax ” group. He supports Hartmann’s 
view that these amoebae have nothing whatever to do with the parasitic 
amoebae {E. histolytica and E. tetrage^ia). 
I conclude this introductory sketch of the literature on the subject 
by a reference to a paper by Major W. G. Liston, I.M.S., as yet un¬ 
published, which he has kindly allowed me to read in manuscrdpt. In 
a culture from liver abscess pus Liston distinguished two species of 
amoebae and I am deeply indebted to him for the suggestion, among 
many others, that the forms seen in the cultures now under consideration 
must, in all pi’obability, represent more than one species. 
II. Technique and material of observation. 
The medium^ used in the experiments now recorded was that of 
Musgrave (1904). The melted agar was poured into small Petri dishes 
which were left partially open to the air for a few minutes until the 
medium had “ set.” Of the plates thus prepared some were directly 
closed, inverted and placed out in various parts of the Hazaribagh 
Central Jail building; others were at first left open, with the agar 
surface completely exposed to the air for varying periods before being 
closed and inverted. 
1 Agar ... ... ... 20 
Sodium chloride ... ... 0'3—0‘5 
Beef extract ... ... ... 0’3—O’o 
Distilled water ... ... 1000 
The reaction of the medium is 1 ®/q alkaline. 
Parasitology iv 
14 
