I always thought that was an early prototype of Lex's artificial life he was attempting to create when Superboy accidentally destroyed that experiment and made Lex bald.
Quote:Vape trick level: Expert
In Challenge of the Superfriends there was a story that told this tale. apparently Luthor created a kryptonite antidote but then some other chemicals in the lab exploded.
Superboy didn't scan the lab with xray vision to see if Luthor was it and used his breath to snuff the flames, but the flames and fumes cost Luthor his hair and in his rage he vowed to never give him the antidote and vowed to destroy him.