The carapace and plastron are usually connected by a "bridge" of bone.
The plastron is joined to the carapace by the sutures of the bridge.
The reptile, aware of danger, had retired between its carapace and plastron.
The use of a species of corslet, (plastron,) to prevent future pressure on the abdomen.
I had myself a great silver bowl, with two goblets, and a plastron of ...