English: PLATE VII.

• Fig. 1. Eight lower jaw of Ctenacodon serratus, Marsh; outer view. The small figure is natural size, and the larger one is magnified four diameters.
• Fig. 2. Right upper jaw of Ctenacodon potens, Marsh.; inner view.
• 3. The same jaw ; seen from below.
• 4. Left lower jaw of Ctenacodon serratus; inner view.
• 5. Incisor, probably of same species ; seen from in front.
• 6. The same incisor ; seen from the side.
• 7. Left lower jaw of Ctenacodon poteois ; outer view.
• 8. The same jaw ; inner view.
• 9. The same jaw ; front view, with its fellow restored in place.

In Figures 2 and 3, a’, first premolar; b, fourth premolar; c, second molar ; m, malar arch. In the lower jaws, a, incisor ; b, condyle ; c, coronoid process ; m, molar ; r, root of incisor ; s, symphyseal surface.

Figures 2, 3, 5 and 6, are four times natural size, and Figures 4, 7, 8 and 9, are three times natural size.