Radiolaria are used to construct an informal zonation (seven zones, numbered one through seven) for Jurassic strata of late Pliensbachian to early Bajocian age from the Fannin, Whiteaves, Phantom Creek and Graham Island formations, Queen Charlotte Islands, British Columbia. The study emphasizes Toarcian Radiolaria, because hitherto little was known of their morphology and distribution; rich, well preserved assemblages of middle to late Toarcian radiolarians have now been recovered from limestones of the Whiteaves and Phantom Creek formations. Ammonites collected as part of a recently completed stratigraphic study of the Jurassic sequence provide excellent control for dating all radiolarian assemblages. Forty-two new species and five new genera of radiolarians are described herein. The sequence of co-occurring ammonites indicates that Zone 1 is late Pliensbachian (Carlottense Zone) and Zone 7 is early Bajocian (Docidoceras widebayense Assemblage Zone and an unnamed interval underlying the Parabigotites crassicostatus Assemblage Zone). Corresponding ammonite zones for radiolarian zones 2 to 6 (Toarcian to Aalenian) have not yet been worked out for North America; thus Zone 2 is early middle Toarcian, Zones 3 and 4 are late middle to early late Toarcian, Zone 5 is late T oarcian, and Zone 6 is Aalenian. Radiolaria from the Queen Charlotte Islands (part of the displaced terrane of Wrangellia) compare well with Tethyan assemblages from western North America, the Mediterranean area and Japan.

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