Abstract
Seven guinea-pigs were inoculated intravenously with a rich suspension of Leishmania enriettii. During the sixth to the seventh week from inoculation, all of them developed lesions within the anterior nasal mucosa and in the vulva or scrotum. In one animal nodules occurred in the forepaws during the tenth week. The histology of the latter showed an epithelioid granuloma with multinucleate giant cells, while in all the others macrophages and monocytes highly parasitized with leishmania bodies, formed the main elements in the granulomatous infiltrate. Lesions seem to develop in the cool, non-hairy areas of the integument and those areas of the nasal mucosa which are constantly bombarded by the inhaled cool air stream. The anterior nasal mucosa, with its leaking venular network, its cool timperature, relative stasis and hypoxia probably provides the optimum micro-environment for the localization, survival and multiplication of the leishmanial protozoon.