The Bell Curve, is a standard for individuals not groups, isn't it? I don't recall them attacking the bell curve, not that I doubt what you say, I just personally don't remember it, but I do recall their upsetment with the findings regarding IQ.
The full name of the famous Murray book is "The Bell Curve: Intelligence and Class Structure in America." It caused considerable consternation among the left and minority rights people when it was published. Not too sure about that upsetment thingy.