Prufrock and the women?

When asked by my English tutor, on Monday night, to interpret the Michaelangelo couplet in Prufrock I dropped the ball. Some of the group felt the women are prostitutes. You can see how that reading is possible; the women appearing, as they do, after the grimy first fragment. Our tutor favours an inside / outside reading. Prufrock is in the "half-deserted streets". The women come and go in a room beyond a window.

The tutor turned to me then said ... you like this poem Dougie, what would you say? To which I answered both readings are possible, although nothing else in the poem supports the prostitute reading.

Poor response Douglas, is what I thought then and now.

Answering the question has been bugging me all week. This much I now know. The famous couplet,

In the room the women come and go
Talking of Michaelangelo

is lifted, almost directly, from something written by the French 'symboliste' Jules Larforge. The original reads,

Dans la piece les femmes vont et viennent
En parlant des maitres de Sienne.

That, of course, shows us something of Eliot's brilliance. And (for reasons I can't quite pin down) argues further against the prostitute reading.

I am being driven nuts, however, in my attempts to source the original. I find reference to it in many Googled places but no citation of the source. That's very, very annoying.
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