"Crista" in Iuv. 6. 422 does not mean ‘clitoris’, ‘labia’, or ‘pubic hair’; and v. 422–423 do not imply manual stimulation of the female genitals: (1) the woman is described as mannish, and this would undermine her characterization; (2) in a close parallel at Mart. 7. 67, a vigorous massage is mentioned after physical exercises and before drinking and vomiting (v. 8); (3) v. 423 resists an obscene interpretation and suggests slapping as part of the massage (сf. Sen. Epist. 56. 1). "Crista" is best taken as a metaphor for a muscular nape: cf. ThLL IV. 1209. 70–77 s.v. (crests of dolphins, whales, and crocodiles) and Scr. physiogn. II. 75 Foerster (of prominent vertebrae): "aspera cervix tamquam cristata"; I. 368 "τραχὺς αὐχὴν ὥσπερ λοφιά."
Denis V. Keyer (Sun,) studied this question.
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