http://www.ozy.com/flashback/john-dillingers-legendary-penis/60348?utm_source=keywee&utm_medium=cpc&kwp_0=27193&kwp_4=159098&kwp_1=164855
Strong memories of hearing this back in the 50s. There'd always be some kid on a school trip vowing to get into the stacks and find it.
The last sentence has MetalDog written all over it...
One theory I heard was that there was a museum for a period of time next to the Smithsonian that had medical curiosities and this was the building that displayed Dillinger's giant junk. People thought it was the Smithsonian but it wasn't. The museum closed up shop and no one knew what happened to the exhibits.