A SPECIFIC tumor of nerve sheath origin was first described in 1908 by Verocay. 1 He christened this tumor "neurinoma" in 1910. Two opposing views of its cellular origin immediately arose: first, that it could only arise from cells of mesodermal origin, namely, the perineural or endoneural components of the nerve sheath, since it contained considerable collagen and reticulin. Penfield 2 held this view, and Tarlov 3 accepted only the term perineural fibroblastoma. On the other hand, Masson, 4 Nageotte, 5,7 Nageotte and Guyon, 6 and Murray and Stout 8 felt that the tumor arose from the sheath cells of Schwann, a view now generally accepted. In 1935, Stout 9 termed it "neurilemmoma." The first parapharyngeal neurilemmoma was reported by Figi 10 in 1933. Koop et al 11 added five cases to the literature in 1947, and four more were added by Slaughter and de Peyster 12 in 1949. Guggenheim,