From The Human Marvel:
Much of what we know of the Maori today comes from the studies and documentations made by Major-General Horatio Gordon Robley. While in New Zealand, Robley befriended the Maori there and used his artistic skills to illustrate and paint scenes of the Maori way of life. Currently the Dominion Museum in Wellington house seventy of his paintings and his sketches provided a basis for Cassells' publication Races of Mankind.
However, Robley is perhaps most well known for his eccentric collection.
The Maori mummified the tattooed heads of their tribesmen and Robley decided to acquire as many as possible. Over the years he built a collection of 35. In 1908 he offered them to the New Zealand Government for £1,000 but his offer was denied. Today, 30 of his heads are in the collection of the Natural History Museum in New York.