Over time, however, Europeans increasingly viewed Melanesians as a distinct cultural, rather than racial, grouping. Scholars and other commentators disagreed on the boundaries of Melanesia, descriptions of which were therefore somewhat fluid. In the nineteenth century, Robert Codrington, a British missionary, produced a series of monographs on "the Melanesians," based on his long-time residence in the region. In his published works on Melanesia, including "The Melanesian Languages" (1885) and "The Melanesians: Studies in Their Anthropology and Folk-lore" (1891), Codrington defined Melanesia as including Vanuatu, Solomon Islands, New Caledonia, and Fiji. He reasoned that the islands of New Guinea should not be included because only some of its people were Melanesians. Also, like Bory de Saint-Vincent, he excluded Australia from Melanesia. It was in these works that Codrington introduced the Melanesian cultural concept of "mana" to the West.