30 
THIRTEENTH REPORT. 
is known as Kala-azar, and the parasite ( Lcish mania clonovani ) is com- 
monly referred to as the “Leishman-Donovan Bodies.” In 190S, a 
similar infection was recognized in young children at Tunis, by C. 
Nicolle, and has been designated as infantile splenic anaemia. l)ur 
iug the past three years this disease has been shown to exist in Italy, 
Greece, Tripoli, Algiers, etc., and there can be no doubt but that it 
is of much more frequent occurrence than has been supposed. 
Nicolle. unlike the Indian investigators, was able to transfer the 
infection to dogs by inoculation with suspensions of the diseased or- 
gans; and, moreover, he succeeded in cultivating the organism upon 
blood agar. With such cultures we were able to infect dogs and repro- 
duce the typical disease, thus establishing beyond doubt the relatiou of 
the cultural flagellates to the Leisliman bodies. Since it had not been 
possible to inoculate the Indian kala-azar into dogs, or to cultivate the 
parasite on blood agar, Nicolle assumed, for the time being, that the 
Tunisian parasite was different and hence proposed to designate it as 
Leishmania infantum . It seems quite reasonable to believe that the 
failure to cultivate and to infect with the Indian parasite was largely 
due to faulty method and that in the end the two parasites will be 
found to be identical. In fact, in his most recent paper on this sub- 
ject. Nicolle has accepted this view of the unity of the parasites. 
A third type of the disease, known as “Oriental sore.” “Delhi boil.” 
“Aleppo button,” etc., is caused by a similar parasite ( Leislvmania - - 
tropica, first discovered by Wright (1903). While the kala-agar 
(Indian and Tunisian) is almost always fatal, this infection is purely 
local and recovery is invariably the rule; in this respect there is a 
marked similarity to the pathogenic and non-pathogenic trypanosomes. 
The cultivation of this organism has also been realized and the disease 
has been successfully transmitted to animals. A similar if not identical 
disease has been observed in Brazil and even at Panama. 
The transmission of these diseases, due to Leishmanias, is undoubtedly 
brought- about through the agency of some blood sucking insect. The 
fact that the parasite can change from the non-motile intra-cellular 
form into the actively motile flagellate, in the test-tube, within 36 hours, 
indicates quite clearly that the parasite must exist outside of the body 
of man and dog, in the flagellate condition, and that, probably, in the 
gut of some insect. Recent work seems to indicate that the dog flea 
is the carrier concerned. 
HEMOCYTOZOA. 
Following up the views of Scliaudinn regarding the relation of the 
intra cellular parasites of the owl to trypanosomes, some investigators 
have endeavored to show that all such parasites were derived from 
flagellates. Whatever, may have been the origin at some remote time 
of the intracellular parasites, one thing is certain, namely, that (apart 
from Leishmania ) no transformation of flagellates into eytozoa, or vice 
versa has been established. 
The researches which revealed the nature of malaria and its mode of 
transmission are, and ever will remain of commanding interest, marking 
as they do a most important epoch in man’s history. These well-known 
studies, however, are not as recent as those which are under discussion 
and lienee need not be considered. 
