Xidelt-- That seems interesting. So ZTA use to be Eta Upsilon Gamma? Or is it the other way around? Or were these chapters that became chapters of ZTA?
I have looked through the Baird's that are available on Google books...so like the 1920s edition. Ha. I also check
www.fratpin.com a lot to see if they find any badges from these defunct NPC or AES members and they often do.
But Beta Gamma is the one that seems to have no information for the modern-day seeker since they might have been absorbed or closed before any thing was written...