Please answer a question about the following article about Anthropology:

During the last three decades of the 19th century a proliferation of anthropological societies and associations occurred, most independent, most publishing their own journals, and all international in membership and association. The major theorists belonged to these organizations. They supported the gradual osmosis of anthropology curricula into the major institutions of higher learning. By 1898 the American Association for the Advancement of Science was able to report that 48 educational institutions in 13 countries had some curriculum in anthropology. None of the 75 faculty members were under a department named anthropology.

What did all the anthropological societies allow their membership to be?
international