I had these as a kid! I've got no idea what happened to them.
Many D&D fans will recognize the bottom two as the rust monster and the bulette.
My assumption is that Gygax, or one of the other DMs in his circle, bought a bunch of plastic 'dinosaurs' and used those as miniatures.
The cute monster in the upper left quadrant looks like the love child of the Tarrasque and a Fiend Folio carbuncle. Carrasque? Tarbuncle? Maybe it has a jewel buried in its head, which can be removed from its dead body by means similar to those needed to extract huge diamonds from the Tarrasque?
Okay, that’s a bit goofy even for me.
It could be fun to stat both the upper figures. What are they?
I’ll probably come back to this. I’m working on my math studies now, and I have some serious writing projects to do a bit later.