A single rearing record was found in material examined, although numerous specimens bore labels that in some way associated them with Baccharis. Four light morphs (three males, one female) emerged on 19 May 1972 from B. pilularis collected at Walnut Creek (Contra Costa County), Calif. The plants were in a stage of vegetative growth, but the exact structure from which the flies emerged is unknown (J. A. Powell, personal communication). However, these data, when compared with similar data for the three other seasonally varying species, suggests that the specimens were reared from stems. This species also has been reared from B. pilularis consanguinea and otherwise associated with B. emoryi A. Gray and unidentified Baccharis species (Foote & Blanc 1963).