"Chondrocranium of Frog (Rana esculenta). y, girdle-bone or os en ceinture; EO, exoccipital; PrO, proötic; QJ, quadratojugal." -Whitney, 1911

Frog Chondrocranium

"Chondrocranium of Frog (Rana esculenta). y, girdle-bone or os en ceinture; EO, exoccipital; PrO, proötic;…