In the course of studies on the insects associated with the Dutch elm disease, several larvae and adults of a cerambycid beetle, Physocnemum brevilineum (Say) were encountered in the bark of both living and recently dead American elm trees. This species is generally recorded as an inhabitant of the outer bark of living elms. Observations show that injury to the living inner bark is rather common, and that occasionally patches of the cambium may be killed. In felled logs, larval behaviour is atypical.