Contents 



Page 



Introduction by Karl V. Krombein, Paul D. Hurd, and David R. Smith v 



Hymenoptera by Karl V. Krombein and Paul D. Hurd, Jr 1 



Symphyta by David R. Smith 3 



Megalodontoidea 7 



Xyelidae 7 



Pamphiliidae 10 



Tenthredinoidea 19 



Pergidae 19 



Argidae 20 



Cimbicidae 26 



Diprionidae 29 



Tenthredinidae 39 



Siricoidea 125 



Syntexidae 125 



Siricidae 125 



Xiphydriidae 130 



Orussidae 131 



Cephoidea 133 



Cephidae 133 



Apocrita by Karl V. Krombein 139 



Parasitica by Paul M. Marsh and Robert W. Carlson 141 



Ichneumonoidea by Paul M. Marsh and Robert W. Carlson 143 



Braconidae by Paul M. Marsh 144 



Aphidiidae by Paul M. Marsh 295 



Hybrizontidae by Paul M. Marsh 313 



Ichneumonidae by Robert W. Carlson 315 



Stephanidae by Robert W. Carlson 740 



Chalcidoidea by Gordon Gordh 743 



Torymidae (except Agaoninae) by E. E. Grissell 748 



Pteromalidae by B. D. Burks 768 



Eurytomidae by B. D. Burks 835 



Chalcididae by B. D. Burks 860 



