I found this USC snapshot a few months ago on eBay. There wasn't any information with it, but it's quite interesting none-the-less.
University of Southern California 'D' 1912. (not sure what the 'D' stands for)
If you look closely, you can see the letters ST in the window. (could the word be Dentist?)
detail
So perhaps the D on the over-sized cloth pennant stands for Dental school.
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There might be an I in front of the S and T.
