This page has been validated.
![](http://upload.wikimedia.org/wikipedia/commons/thumb/6/6e/The_Osteology_of_the_Reptiles_p30.png/400px-The_Osteology_of_the_Reptiles_p30.png)
Fig. 16. A, Dimetrodon incisivus Cope. Pelycosaur: left mandible, outer side. B, Dimetrodon incisivus Cope. Pelycosaur: left mandible, inner side. C, Dimetrodon incisivus Cope. Pelycosaur: right mandible, inner side. D, Labidosaurus hamatus Cope. Cotylosaur: right mandible, inner side. E, Labidosaurus hamatus Cope. Cotylosaur: right mandible, outer side.
30