PLOWRIGHT, C.M.S., R.C. PLOWRIG H.T., and P.H. WILLIAMS - Replacement of Bombus muscorum by Bombus pascuorum in northern Britain? …985-990
NICOL, R.W., J.T. ARNASON, B. HELSON, and M.M. ABOU-ZAID - Effect of host and nonhost trees on the growth and development of the forest tent caterpillar, Malacosoma disstria (Lepidoptera: Lasiocampidae) …991-999
SILK, P.J., L.P.S. KUENEN, A.R. ALFORD, G.C. LONERGAN, and G.G. GRANT - Sex pheromone components of the oak leaf shredder, Croesia semipurpurana (Lepidoptera: Tortricidae) …1001-1008
HAMMOND H.E.J. - Arthropod biodiversity from Populus coarse woody material in north-central Alberta: a review of taxa and collection methods …1009-1033
LAMB, R.J., and P.A. MACKAY - Photoperiodism and life cycle plasticity of an aphid, Macrosiphum euphorbiae (Thomas), from central North America …1035-1048
LAMB, R.J., I.L. WISE, and P.A. MACKAY - Photoperiodism and seasonal abundance of an aphid. Macrosiphum euphorbiae (Thomas), in oilseed flax …1049-1058
GOETTEL, M.S., G.M. DUKE, and D.W. GOERZEN - Pathogenicity of Ascosphaera larvis to larvae of the alfalfa leafcutting bee, Megachile rotundata …1059-1065
TORRES, F., S.F. GAYUBO,J. TORMOS, and J.D. ASIS - Description of the mature larvae of three Hoplitis (Hymenoptera: Apoidea: Megachilidae) …1067-1078
NEIL, K.A., S.O. GAUL, and K.B. MCRAE - Control of the English grain aphid [Sitobion avenae (F.)] (Homoptera: Aphididae) and the oat-birdcherry aphid [Rhopalosiphum padi (L.)(Homoptera: Aphididae) on winter cereals …1079-1091
ORTEGO, J., J.M. NIETO NAFRIA, and M.P. MIER DURANTE – Blanchardia poikila gen. nov., sp. nov. (Hemiptera: Aphididae, Macrosiphini) in Mendoza, Argentina …1093-1103
BARCLAY, H.J. - Assessing natural selection in white pine weevils (Pissodes strobi Peck) (Coleoptera: Curculionidae) for overcoming resistance in trees: an evolutionary model …1105-1120
BROOKS, S.E., and J.D. SHORTHOUSE - Biology of the rose stem galler Diplolepis nodulosa (Hymenoptera: Cynipidae) and its associated component community in central Ontario …1121-1140
VICKERY, V.R. - Two new species in the genus Diapheromera (Phasmatoptera: Necroscioidea: Heteronemiidae: Heteronemiinae) from Baja California, Mexico …1141-1149
SONGA, J.M., and N.J. HOLLIDAY - Laboratory studies of predation of grasshopper eggs, Melanoplus bivittatus (Say), by adults of two species of Pterostichus Bonelli (Coleoptera: Carabidae) …1151-1159
QUEDNAU, F.W. - Taxonomic notes on three black-bordered Myzocallis from oak in North America with descriptions of two new species (Homoptera: Aphididae) …1161-1171
ONYABE, D.Y., and B.D. ROITBERG - The effect of conspecifics on oviposition site selection and oviposition behaviour in Aedes togoi (Theohold) (Diptera: Culicidae) …1173-1176
SCIENTIFIC NOTE
GRIES, G., R. GRIES, and P.W. SCHAEFER - Pheromone blend attracts nun moth, Lymantria monacha (Lepidoptera: Lymantriidae), in Japan …1177-1178
ERRATUM …1179
INDEX TO VOLUME 129 …1181
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