Abstract
Representatives of the families Braconidae and Pteromalidae were present in association with broods of Ips pini Say and Ips perroti Sw. The identifications and information on distribution and hosts were kindly supplied by O. Peck and W. R. M. Mason of the Systematic Entomology Unit in Ottawa. Additional information on hosts and distribution were obtained from Hymenoptera of America by Muesebeck, Krombein, Towns, et al. (1951).