SUMMARYSchode, R., and J. L. McKean. 1973. Distribution taxonomy and evolution of the gardener bowerbirdsAmblyornisspp in eastern New Guinea, with descriptions of two subspecies. Emu 73: 51–60.Amblyornis macgregoriaeandA. subalarisare effectively altitudinally allopatric on both scarps of the Owen Stanley Range. The hitherto poorly known distribution of the two species in the eastern Owen Stanley Range is documented in some detail. Both species meet between altitudes of 1,200 and 1,400 m, withA. macgregoriaeoccurring in primary mixed montane andNothofagus-forest above, andA. subalarisin primary fagaceous hill-forest below. The juxtaposition ofA. macgregoriaebowers on ridges and ofA. subalarisbowers on slopes below the crests of ridges in areas of abutment suggests competition between the two species; altitudinal displacement ofA. subalarisbyA. macregoriaeis inferred.The evolution and distribution ofA. macgregoriaeandA. subalarisare interpreted in terms of alternating disjunction and conjunction of one ancestral stock brought about by the altitudinal expansion and contraction of forest-zones during climatic oscillations of Pleistocene times. The present grouping of subspecies ofA. macgregoriaein eastern New Guinea is probably the result of the most recent (post-glacial) isolation of various populations by passes of low altitude and valleys of alien habitat.A. subalarisis monotypic.Two new subspecies are recognized:A. macgregoriae komhok, in the Kubor-Mt Hagen-Bismarck Ranges, andA. m. nubicola, in the extreme eastern Owen Stanley Range.