The Role of the Stolviach Wall in the Exogenous Development of Plasmodium Galllnaceum as Studied by Means of Haelviocoel Injections of Susceptible and Refractory Mosquitoes

After the discovery by Ross (1898) of the role played by mosquitoes in the transmission of plasmodia, the details of the life cycles of malaria parasites in both the vertebrate and invertebrate hosts have become so widely accepted that the literature now gives the tacit impression that the parasite can not deviate from the routine pattern. The stomach wall in mosquitoes has been given a role of prime importance in the development or the inhibition of the parasite in its exogenous cycle. In such a role it became the most important determining factor in the susceptibility of mosquitoes. In the experiments reported here, which were designed to study the innate immunity or susceptibility of certain mosquitoes to malaria, it has been shown that, although the prescribed route may be necessary in natural infections, the parasite is able to deviate from this cycle. The barrier of the stomach wall was by-passed by inoculating the exogenous stages, from gametocytes to sporozoites, into the