I am so glad you mentioned these! I was planning to if nobody else did. 
Katherine Ross
(Damn you, Sam Elliott)
No, still photos from Breakfast At Tiffany’s exist.
Here’s the list so far. Keep 'em coming…
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Pier Angeli
Barbara Bain
Brigitte Bardot
Julie Christie
Catherine Deneuve
Donna Douglas
Jane Fonda
Ava Gardner
Francoise Hardy
Audrey Hepburn
Grace Kelly
Hedy Lamarr
Sophia Loren
Jayne Mansfield
Ann Margret
Marilyn Monroe
Elizabeth Montgomery
Nichelle Nichols
Debra Paget
Diana Rigg
Katherine Ross
Jean Simmons
Elizabeth Taylor
Natalie Wood
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That’s Hedly Lamarr
Yeah – I know. But I included the link.
I always go more for Gina Lollobrigida when this subject comes up.
If I forget to vote in the poll, click Marilyn Monroe for me, please. 
Rita Hayworth, Fred Astaire’s favorite dancing partner, will be a top choice when you do the 1940’s. But although Salome came out in 1953 (and she made movies even in the 1960’s and 1970’s) Ms. Hayworth was probably past her pulchritudinous prime by 1950.
How about Ingrid Bergman? I think she’s beautiful.
I’ll try to remember about Marilyn!
I saw Rita in several of her late-1950s things. Rita Hayworth (1918–1987) shows several where she was still quite the femme fatale. Pal Joey especially.
In any case, I’ll add her to the list. Others may see their way clear to vote for her. But I’m thinking one vote per Voter is the way to do this poll. Multiple choice polls get hard to control. 
Amen! No doubt. Good call.
We’re up to 30 names now. If we go a whole 24 hours with no new candidates, or when we get to 50, I’ll put up a poll. One vote per voter!
Make your new nominees matter, please!
No love for Raquel Welch?
Thanks for the mention! She’s another I was going to mention if nobody else did. Your basic Stone Fox! 
I identify her mostly with the 1940s.
I tend to agree, especially when her looks were the main attraction, but Ingrid Bergman (I) (1915–1982) was still good looking on into her 50s as the list of her movies would suggest. For my money she was one of the very few who kept her looks on into her older age. Classic beauty.
Jean Seberg is another one I don’t see mentioned yet.
Yep!
No contest, IMHO.