Someone with whom I’ve corresponded (and I’m very sorry to have lost track of who you are — berate me in e-mail or comments if you ‘cuz I deserve it) pointed out to me once that the casket of glass in which Snow White was temporarily held might make the tube-girl meme older than generally thought. It seemed like a good thought to me at the time.
Someone else out there evidently thought so as well:
Although they do appear to be one dwarf short. (Oh, stop…) In addition to European folk tales and the tube-girl meme, it would appear that Wally Wood‘s immortal parody Disneyland Memorial Orgy was a key inspiration.
The image crops up at various places on the Internet, but I found it in this post at Janitor of Lunacy.