What is "crassocephalum"

Crassocephalum is a genus the common names of whose members include ragleaf, thickhead, and bologi. Several species are raised as leaf vegetables and used for medicine, especially in West Africa. Similar to Senecio, but differing in never having ray florets. A calyculus of short bracts (c.1/4 to 1/5 of the length of the inner phyllaries) is present. The genus is typically thistle-like in appearance, but all parts are soft and not spiny.