Henry W. Bates conveys to ARW’s mother news of the death of her son Edward (Herbert Edward), ARW’s younger brother, who reached camp while ARW was away upriver. He had contracted yellow fever; Bates was with him, obtained physician’s care, but after a few days Herbert perished from the “black vomit,” the most lethal form of the disease. Bates reports that Herbert was well looked after to the end.

Bates informs ARW’s mother of the death of youngest son Edward Herbert Wallace from yellow fever; his insect collections will be sent home by next vessel. Herbert didn’t realize “that his case was serious until a few hours before his death,” and then he remarked that it was “sad to die so young.” About a third of population here wiped out by smallpox.

Long wait for and final arrival of a ship to Macassar; arrival of Bates' letters from Ega (now Teffé) Brazil, and copy of Zoologist; geographical distribution of insect species in the islands of the Malay archipelago; relative scarcity of Lepidoptera; comparative numbers and types of insect species in Malay archipelago and Brazil; details of insects collected, including new butterfly Ornithoptera Brookeana (Wallace), Rhyncophorae, Carabidae, Anthribidae, Bupestridae, Cleridae, Longicornes and many others, total number of insect species collected estimated at 6,000, specimens over 30,000; desire to collect all world Longicornes for study; importance of recording location of capture of specimens; separation of collections from different localities; desire for future comparison of data and exchange of specimens with Bates; Orang Utans; comparison of types of forest plants, people and customs in Amazon and Malay archipelago; scarcity of edible fruit in the East; delicious Durian; Madame Pfeiffer's insect collection; regards to Spruce.

No summary available.

Receipt of mail from home including letters from Bates and Darwin; cleaning and packing of collections from Aru; detailed account of numbers, types and locations of insects collected, including first serious collection of very small beetle species (Staphylinidae etc) at Macassar; comparison of data sent by Bates with his own; reaction to ARW's paper "On the succession of species", approving letter from Darwin; benefit of Darwin's proposed publication on species and varieties; boundary between two distinct faunas in Malay Archipelago; proposed expeditions to Gilolo island [Halmahera] and New Guinea; advantages of Amboyna as a base; battles of Balaclava and Inkerman; Britain - India meeting [British rule in India]; insects in the Andes.

Bates' safe arrival (in England); hopes Bates will write a Fauna of the Amazon Valley; ARW's own plans for a similar work on the Malay Archipelago; hopes for exchange of duplicate specimens; paper on principles of Geographical distribution in the archipelago sent to the Linnean Society.