Hume exchanged skins with other collectors. A collection made principally by Hume that belonged to the Earl of Northbrook was gifted to Oxford University in 1877. One of his correspondents, Louis Mandelli from Darjeeling, stands out by claiming that he was swindled in these skin exchanges. He claimed that Hume took skins of rarer species in exchange for the skins of common birds but the credibility of the complaint has been doubted. Hume named "Arborophila mandelli" after Mandelli in 1874. The only other naturalist to question Hume's veracity was A.L. Butler who met a Nicobar islander whom Hume had described as diving nearly stark naked and capturing fish with his bare hands. Butler found the man in denial of such fishing techniques.