[bbg]

This reminds me of part of Stephen Jay Gould's The Mismeasure of Man, which talks about "trained" employees at Staten Island (or other points of entry for immigrants) in the nineteenth century, who could spot mental deficiency by looking at the shape of the head (craniometry, but without measurement, just eyeballing). I'm writing this from memory, so I can't go into detail, and I don't have a link to this particular passage. But a significant number of immigrants were put on boats back to Europe just because of the snap judgment of these spotters.

http://en.wikipedia.org/wiki/The_Mismeasure_of_Man