Alexey Sklyarenko: "She [Lucette] complained to her governess who, completely misconstuing the whole matter (which could also be said of her new composition), summoned Van and from her screened bed, through a reek of embrocation and sweat, told him to refrain from turning Lucette's head by making of her a fairy-tale damsel in distress." (1.23)
Mlle Larivière probably uses the phrase tourner la tête. As I pointed out before, this phrase was used by Pushkin in a four-line French poem written in 1821:
J'ai possédé maîtresse honêtte,
Je la servais comme il <lui> faut,
Mais je n'ai point tourné de tête, -
Je n'ai jamais visé si haut.

JM: In the translation of Pushkin's "French poem" the expression is, as you wrote down, "tourné de tête" (instead of la"), or was it a typo?

I wonder if Nabokov's original meaning concerning Mlle Larivière's warning, clearly intended as signifying what A.Sklyarenko has set into French, is correctly stated in English by Nabokov.