Abstract
Two manners in which parasitic Hymenoptera gather reproductive proteins are described. Hydropic species gather all protein necessary for reproduction as larvae. Only 5–10% of the material necessary to form a viable first instar larva is put into each egg; the remainder is gathered by the egg within the host. Egg storage is in the lateral oviducts, handling times are short and egg production is independent of host density. Three Bathyplectes spp. are examples of hydropic parasitoids. Anhydropic species gather some or all protein as adults, often by host feeding. All the material necessary for the formation of a viable first instar larva is stored within the egg. The eggs are held in the ovary until laid. Handling times are longer and continued egg production is dependent upon host density. Tetrastichus incertus (Ratzeburg) is an anhydropic parasitoid.Hydropic parasitoids appear best suited for biological control efforts in ephemeral situations (i.e. cotton or alfalfa). Anhydropic parasitoids appear best suited for biological control efforts in stable situations (i.e. citrus or walnuts).