In the course of our experiments on the development of flagellates in sandflies fed on animals infected with Chinese Kala Azar (Patton & Hindle, 1927), numerous attempts were made to infect hamsters by means of these insects. The life-history of the flagellate in
Phlebotomies major
, in which insect there is a rapid growth of the parasites towards the anterior part of the alimentary canal, ending with infection of the mouth parts, strongly suggests that the parasite is transmitted by the bite of an infected fly, consequently many of our experiments consisted in feeding sandflies on infected animals and subsequently on normal ones. The possibility of other methods of infection was kept in mind, however, and on the analogy of
Trypanosoma lewisi
in the rat flea, attempts were made to infect animals by feeding them with sandflies containing flagellates, as it is conceivable that the infection may reach the body through the alimentary canal. In addition infection might be produced by parasites, set free by crushing the insect, entering the body either by means of the open wound caused by the bite of the fly, or through an excoriated part of the skin. The results of preliminary experiments with culture flagellates (Hindle & Patton, 1926) showed that, although the hamster could be readily infected by intraperitoneal inoculation of these forms, the subcutaneous and percutaneous methods of infection succeeded only occasionally. From these experiments one would not expect the bite of an infected sandfly to produce infection except in rare cases, for obviously the parasites are only introduced subcutaneously when the insect feeds, and therefore, in most instances, the contents of infected flies were inoculated intraperitoneally into hamsters in order to see whether the flagellates were infective or not. Most of our experiments in 1926 were made with
Phlebotomussergenti
, which is not such a favourable host as
P. major
var.
chinensis
, and in view of the fact that flagellates were never observed in the pharynx of the former species, it is not surprising that all feeding experiments gave negative results.
P. major
has a comparatively short season, and the few experiments we were able to perform are not sufficient to indicate the efficiency of this species as a carrier.
PARTIAL PREPARATORY STAGES OF APATELA LOBELLÆ, Guen