This figure was part of the original "small" mold group. The mold has two cavities for making two essentially identical Dimetrodons. Right from the start Marx clearly expected to sell a lot of Dimetrodons. But it seems that wasn't enough, because when the "revised" mold group appeared, there was another Dimetrodon. So Marx was making three times as many Dimetrodons as most anything else. Both molds stayed in production throughout the original production period and the reissue period. The three distinct Dimetrodons are essentially identical. All were made in three-segment molds (left, right, ventral). They can be distinguished, although there's little practical reason to do so. Examine the area on the tail, where the markings - DIMETRODON on the left, 7'LONG on the right - intersect the vertical lines on the tail. The lines are in different locations relative to the letters. 
Dimetrodon (b), "small" mold group, original issue Dimetrodon (c), "revised" mold group, original issue And of course they didn't change much when they were reissued. Here's the whole lineup - 
Dimetrodon (b) original issue • Dimetrodon (a) reissue • Dimetrodon (a) original issue Dimetrodon (b) markings - DIMETRODON (left side of tail), 7' LONG (right side of tail). Seven feet seems a tad on the small side; he was probably closer to 10 feet overall. This is another non-dinosaur. Dimetrodon was a synapsid, or one of the "mammal-like" reptiles. Details of the skull, jaws, and teeth are what tell the story. More about how Dimetrodon fits in the scheme of things is here. |