Can. Ent. 107: 499-528 (1975) This is the first paper on Canadian Cretaceous chalcidoid fossils of the families Mymaridae, Trichogrammatidae, and Tetracampidae, based on 54 specimens representing 12 species from Manitoba and Alberta. Four new subfamilies are proposed, Triadomerinae (Mymaridae), Baeomorphinae, Distylopinae, and Bouceklytinae (Tetracampidae). Descriptions and remarks are given for Archaeromma nearctica n. gen., n. sp.; A. minutissima (Brues) (Mymaromminae); Triadomerus bulbosus n. gen., n. sp.; Carpenteriana tumida n. gen., n. sp.; Protooctonus masneri n. gen., n. sp. (Mymaridae); Enneagmus pristinus n. gen., n. sp. (Trichogrammatidae); Distylopus bisegmentus n. gen., n. sp.; Baeomorpha distincta n. gen., n. sp., B . dubitata Brues (transferred from Scelionidae, Prototrupoidea), B. elongata n. sp., B. ovatata n. sp. and Bouceklytus arcuodens n. gen., n. sp. (Tetracampidae). A list of all previously known fossil Chalcidoidea is provided. A table of primitive and specialized conditions of characters studied is given. The possible lines of phylogeny of families and genera of these fossils are discussed. Keys to the pertinent families and subfamilies and to the fossil species of Baeomorpha are provided. Photomicrographs of species treated are included.

The genus Euderus Haliday in America north of Mexico consists of five subgenera, Secodelloidea Girault, Euderus Haliday, Euderoides n. subgen., Neoeuderus n. subgen., and Leipocrossus n. subgen. and 25 species; 13 species are described as new and are as follows: Euderus (Secodelloidea) canadensis, E. (Euderoides) purpureus, E. (Neoeuderus) viridilineatus, E. (Neoeuderus) magnificus, E. (Leipocrossus) californicus, E. (Euderus) solidaginis, E. (Euderus) vockerothi, E. (Euderus) chillcotti, E. (Euderus) masoni, E. (Euderus) fuscedinellae, E. (Euderus) pecki, E. (Euderus) glaucus, and E. (Euderus) alaskensis. Species groups of albitarsis and solidaginis form two natural groupings within the genus Euderus s. str. Keys to subgenera and species, distribution, and host records are included.

Eighteen parasitoid species were found associated with obliquebanded leafroller, Choristoneura rosaceana (Harris), and three-lined leafroller, Pandemis limitata Robinson, from 1982 to 1984, on apple and other host plants in the southern interior of British Columbia. The leafroller parasitoids included a Glypta Gravenhorst species (Hymenoptera: Ichneumonidae), Diadegma eureka (Ashmead) and Diadegma interruptum pterophorae (Ashmead) (Hymenoptera: Ichneumonidae), and Hemisturmia tortricis (Coquillett) (Diptera: Tachinidae). The two leafroller species were found on 18 wild host plants from 10 plant families.

This study provides information on species of Pnigalio Schrank found in America north of Mexico: Pnigalio longulus (Zetterstedt), a Palearctic species, is recorded from the Nearctic for the first time; the previously unplaced species of Pnigalio of Miller (1970) are discussed. Seventeen species are recognized, of which the following eight are described as new: Pnigalio levis, P. brachysellus, P. elongatus, P. glaber, P. rugatus, P. neolongulus, P. boharti, and P. albiformis. A key to species, illustrations, distribution data, and host records are included.

The proposed new subfamily Himalocynipinae based on Himalocynips vigintilis n. gen., n. sp., from Nepal, is described and illustrated. Several unique characters of Himalocynipinae are discussed.