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In the plant kingdom, Compositae, with 1 000 genera and 20 000 species, is a great family. It has two subfamilies, Carduoideae kitam, with 12 tribes,and Cichorioideae Kitam, with only 1 tribe, Lactuceae Cass. In Lactuceae Cass, Lactuca is a great genus,wh