Letters from Alfred Russel Wallace to Philip Lutley Sclater regarding the purchase of a joint residential estate, extracts read at meetings of the Zoological Society of London, papers for the Proceedings of the Zoological Society of London and Natural Science, his publication on 'Monkeys - their structure, affinities and distribution', a shipment of birds for the Society, improvements to the Gardens of the Zoological Society of London, notes on the Umbrella Bird, his election as a Fellow, papers on marine mammals, opinions on theories by Darwin, Birds of Paradise, and a list of butterflies of Costa Rica