I must be getting old because I just barely remember her.
I recognize the brunette in the middle as the french accent chick in the episode where the newly rich boys demolish their hotel room. Is this promo shot from that episode? And what does the scrawled notation in the lower left corner indicate?
The French accent actress you're probably thinking of is Nanette Bordeaux and the short A MISSED FORTUNE. Here's a picture of her.
The actress in the middle of the pic you posted is Dorothy Appleby, the short IN THE SWEET PIE AND a PIE, and yes, that's a much younger Ethelreda Leopold on the right.