0. GC. Marsh—American Jurassic Mammals. 347 
EXPLANATION OF PLATES. 
PLATE VII. 
FiGuRE 1.—Left upper jaw of Allodon laticeps, Marsh ; outer view. 
Figur 2.—The same specimen ; seen from below. 
Figure 3.—Left upper jaw of same species; inner view. 
FiguRE 4.—The same specimen; seen from below. 
FicuRE 5.—Left upper jaw of same species; outer view. 
Figur& 6.—The same specimen; seen from below. 
FIGURE 7.—Right premaxillary of Allodon fortis, Marsh ; outer view. 
FIGURE 8.—The same specimen ; seen from below. 
FIGURE 9.—The same specimen ; seen from in front. 
FIGURE 10.—The same specimen ; inner view. 
FigurE 11.—Portion of left upper jaw of Allodon fortis; outer view. 
FIGURE 12.—The same specimen; seen from below. 
FIGURE 13.—The same specimen ; inner view. 
FIGURE 14.—Lower incisor of Allodon fortis ; side view. 
FIGURE 15.—The same incisor; seen from in front. 
a, last incisor; a’, second premolar; 6, fourth premolar; 0’, third premolar ; 
c, second true molar; c’, first molar; /, antorbital foramen; m, malar arch; 
s, suture with maxillary. 
Figures 1-4 are four times natural size; 5 and 6, six times natural size; 7-15, 
three times natural size. 
PLATE VIII. 
FiguRE 1.—Right lower jaw of Cienacodon serratus, Marsh; outer fom: 
The small figure is natural size, and the larger one is magnified four diameters. 
FIGURE 2.—Right upper jaw of Ctenacodon potens, Marsh; inner view. | 
FIGURE 3.—The same jaw; seen from below. 
FIGuRE 4.—Left lower jaw of Ctenacodon serratus; inner view. 
FicuRE 5.—Incisor, probably of same species; seen from in front. 
FIGURE 6.—The same incisor; seen from the side. 
Figure 7.—Left lower jaw of Ctenacodon potens; outer view. 
FIGURE 8.—The same jaw; inner view. 
Figure 9.—The same jaw; front view, with its fellow restored in place. 
In figures 2 and 3, a’, first premolar; 5, fourth premolar; c, second molar; 
m, woalar arch. In the lower jaws, a, incisor; 6, condyle; c, coronoid pro- 
cess; m, molar; 7, 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. 
