Page:Transactions of the Royal Society of Tropical Medicine and Hygiene, volume 2 (3).djvu/29

ON KALA-AZAR 133 Dr. Low, after thanking Captain Patten for his inter- esting paper, said he would hke to ask him a question on the development of the forms illustrated on the black- board. He could not himself say that it was definitely certain yet that the Leishman parasite was a herpeto- monas, though it had, as the lecturer had pointed out, many resemblances, especially in the flagellate form. It did not appear that these forms of herpetomonas repre- sented went through any sexual development, but simply reproduced by fission in the body of the fly. On the other hand, the Leishman body was a cellular parasite and apparently to go through its development must have an extracorporeal sexual life-cycle in the bug. He thought there was enough evidence (apart from resemblances) to diff'erentiate it into a different parasite altogether. One must be careful with regard to resemblances. In trypano- somes he had seen forms which were really very diflicult to distinguish from the young forms of Leishman-Donovan bodies, and therefore he thought superficial resemblance between the first stages of parasites should not be allowed too much weight. He (Dr. Low) was certain that the parasite of Oriental sore was different from that of kala- azar. He had recently seen two cases of Oriental sore from Persia. He had asked one of them whether kala- azar existed there, and the answer was most emphatically, that it did not, or at least was very- rare.

He did not know anything about the new parasite of infantile splenomegaly ; he had seen the one of Darling, and he was inclined to think it distinctly a different para- site from the Leishman-Donovan body.

As regards the life-history of the parasite in the bug, he found it very interesting, but it would be of great advantage if one could prove transference back from the bug. Experiments on dogs had always failed, but if we