[Helminthological research of M. M. Zavadovskiĭ].

M. M. Zavadovsky (1891--1957) embriologist and geneticist is one of the founders of the experimental helminthology in the USSR. Using original methods he in twenties--thirties studied the structure of the egg membranes in some parasitic nematodes, proved the necessity of the access of free oxygen for the development of their eggs, studied the role of some environmental factors in the ontogenesis of nematodes. On this basis Zavadovsky worked out certain recomendations for the prophylaxis of nematodose of agricultural animals. His works have not lost their significance up to now.