128 DISCUSSION
With regard to Leishmaniasis, he would not only
include under the same term the epidemic kala-azar of
Assam, the infantile splenic form described by Nicolle
from Tunisia, the lung form seen by Darling in Panama,
and the cirrhotic liver form of Rogers, but also the
cutaneous form of a hundred names now generally called
" Oriental sore."
It would not be the first time in the history of medicine that the discovery of the specific agent enabled them to ascribe to a common cause unlike morbid mani- festations previously looked upon as entirely distinct dis- eases. He need but mention tuberculosis and syphilis.
Concerning the identity of Oriental sore and kala-azar, he had already said that it had been opposed on account of difference in geographical distribution. So far as he could judge from the available data, the facts of geo- graphical distribution were decidedly in favour of a relationship between the two forms of disease ; but, to thoroughly understand the geographical data, it was necessary to master the complex oecology of the disease, and especially the different local causes which determined the prevalence of one or other form of the distemper.
He wished above all to discuss the striking difference between the local benign form called "Oriental sore" and the deadly general form called kala-azar, to endeavour to show that it was by no means opposed to a common cause, but, on the contrary, greatly in favour of it. There were many analogous examples to illustrate the relation- ship and explain it in the most satisfactory manner.
They might take tuberculosis as an example. The multitudinous forms in which that infection might mani- fest itself were well known. How different were the local cutaneous manifestations from the general infection ! They all knew perfectly well that when transmitted by
