When did Thomas do hers? In otherwords who copied who???
http://en.wikipedia.org/wiki/The_Snail
The Snail or The Snail (L’escargot), by Henri Matisse, Nice-Cimiez, Hotel Regina, [summer 1952-early] 1953, Gouache on paper, cut and pasted, on white paper, 9’4 3/4” x 9’ 5” (287 x 288 cm) collection Tate Gallery, London.[1] It consists of a number of colored shapes, arranged in a spiral pattern, as suggested by the title. During the early to mid-1940s Matisse was in poor health. Eventually by 1950 he stopped painting in favor of his paper cutouts. The Snail, is a major example of Matisse’s final body of works known as the cutouts.[2]
She did hers 10 years AFTER.
Alma Thomas, Watusi (Hard Edge), 1963: A prominent abstract painter of the 1960s and 1970s and the first African-American woman to have a solo art exhibition at New York’s Whitney Museum. Born in Columbus in 1891, racist attitudes and a poor education system for African-Americans at that time hampered her childhood, but she excelled at architectural drawing.