' 330 O. C. Marsh— American Jurassic Mammals. 
The upper molar series in the type specimen of Adlodon is 
well shown in Plate VII, figures 1 and 2. The five premolars 
have tuberculate crowns, and all appear to be inserted by two- 
fangs. The first and second have each one external, and two 
internal cones. The third premolar has a small additional cusp. 
These three premolars diminish in size from before backward. 
The next premolar, or fourth, is much larger, and has its crown 
flattened on the inner side. There are three tubercles on the 
outer border, and four, on the inner margin. The fifth in the 
series is still larger, and has a more rounded crown. There are 
three lobes on the outer side, and the same number on the 
interior face. 
The two true molars have low crowns, which are divided 
into an outer and inner half, by a deep-worn groove. Each 
half bears three low tubercles, of nearly equal size. The 
last molar has its longitudinal groove on a line with the inner 
margin of the other teeth. 
The superior incisors of this genus now known are repre- 
sented in the detached premaxillary of Adlodon fortis, Plate 
VII, figures 7-10. The first incisor was very small. The 
second was the main front tooth, much larger than the third. 
In the type specimen of Adlodon, represented in Plate VII, 
figures 1 and 2, no suture is visible behind the first smal! tooth 
(a), hence, this may possibly be a weak canine instead of the 
third incisor. In Adllodon fortis, figure 7, and also in the type 
of Bolodon, Owen, the suture between the premaxillary and 
maxillary is distinct. 
The large second incisor of A//odon is a peculiar tooth, and 
was evidently exposed to the full wearing action of a strong 
lower incisor, somewhat similar to that of a rodent. This lower 
tooth has not been found in place, but the one represented in 
Plate VII, figures 14 and 15, may, with considerable probability, 
be referred to this position. The remaining lower teeth have 
not been found associated with the upper jaws, but they evi- 
dently resembled those of Ctenacodon, in some of their most 
important characters. 
In comparing Adlodon with Bolodon, we evidently have two 
nearly related forms. So far as at present known, Adlodon has 
three incisors instead of two, a larger number of teeth in the 
premolar and molar series, and likewise shows other differences 
of less importance. 
The affinities of these peculiar fossils, and the inferences in 
regard to their habits and food, which may be drawn from the 
specimens now known, will be fully discussed by the writer 
elsewhere. 
