We reported 1 the development of herpetomonad flagellates in Chinese sandflies fed on hamsters infected with kala azar. In the present paper are summarized the results of various kala azar transmission experiments performed in 1925 and 1926.

The three species of sandflies, for the determination of which we are indebted to Professor R. Newstead, are: Phlebotomus major var. chinensis Newstead; P. sergenti var. Newstead (Phlebotomus “C” of our previous report), identical with an unnamed variety described from Mesopotamia 2 ; P. perturbans var. Patton 3 (Phlebotomus “B”). This latter species we have never fed on man or other mammals in the laboratory, but it readily engorges on toads.

In the following experiments we tested the hypothesis that Phlebotomus sandflies becoming infected by sucking the blood of kala azar patients are then able to transmit the disease to other persons by their bites. The first was fed upon heavily infected hamsters. Later they were fed upon tested negative hamsters.

As P. sergenti became infected with Leishmania only rarely, following “natural” feeds, as contrasted with the very large proportion of infected P. major, a technique described elsewhere 4 was devised for feeding sandflies artificially with rich suspensions of Leishman-Donovan bodies. The apparatus consists essentially of a cork vise for immobilizing the sanctfly and an adjustable holder for the feeding pipette, the end of which is fitted over the insect's stylets. Freshly defibrinated rabbit blood was centrifuged and the serum removed. Spleen tissue from a hamster heavily infected with Leishmania was ground up in this serum. A volume of spleen-serum suspension equal to that of the serum, originally removed, was then added to the rabbit corpuscles. The sandflies engorged readily. Infections with Leishmania were produced in all three species. Those for P. perturbans are not reported here, since feeding experiments on mammals have not proved possible with this species.