Pp. 7 -- Part 1. Principles involved in designating the types of genera of parasites : Introduction -- Historical review of type description -- Axioms relative to type species -- Rules and recommendations concerning types -- A. Genera for which types are designated or implied in the original publication -- B. Genera for which types have been selected in later publications -- C. Genera for which no type has been definitely selected. pp. 10-80 -- Part 2. List of generic names, chiefly nematodes, with their original and type species. pp. 81-150 -- Addenda. pp. 150.