The apple mealybug, Phenacoccus aceris Sig., has been a pest of apple trees periodicallv since an outbreak was reported by Gilliatt in 1935. The writer investigated mortality in its population during the summer of 1966 in connection with the current sporadic outbreak in the Annapolis Valley. Decline of outbreaks was attributed bv Marshall and Pickett (1944) to attacks by the parasite Allotropa utilis (Mues.) (Hymenoptera: Platygasteridae), and the abundance of this parasite in the current upsurge in mealybugs suggests it is an important factor. Mr. K. H. Sanford (personal communication) estimated approximately 58% of the mealybugs in the winter of 1965–1966 and about 80% in the winter of 1966–1967 were parasitized by this species.