3 6 4 
The Ohio Naturalist. 
[Vol. VIII, No. 8, 
In figure 1 all bones of the side of the skull are foreshortened 
since in a direct lateral view they lie at an angle of about thirty- 
five degrees with the median line of the skull. The suborbital, 
mandible, dorso-laterals, and clavicular are foreshortened dorso- 
ventrallv. They lie at an angle of about forty-five degrees with 
the median longitudinal vertical plane of the body. This angle 
was obtained from an undistorted dorso-median of the same 
species. The relations of the other bones to the dorso-median 
make it certain that it is approximately correct. In figure 2 
the bones are represented as lying in one plane almost exactly as 
they lie in the specimen and all bones are drawn in proportion. 
The sutures in the skull are not distinct. The. median occi¬ 
pital and external occipital are the only bones of which it is possi¬ 
ble to make out the outline distinctly. 
The suborbital as shown in figure 2 lies just as it does in the 
specimen. The anterior end is restored from the anterior end of 
the left suborbital. The notched anterior end has not been fig¬ 
ured or described previously that I am aware. In the interior 
of the notch the bone is fifteen millimeters thick and apparently 
articulated with some other bone. The anterior slime canal 
seems to be continuous with the anterior slime canal of the top of 
the skull. The bone is usually broken where the slime canal 
crosses it and the anterior end lost. Behind the orbit the sub¬ 
orbital articulates with the postorbital for a short distance and 
then does not touch the margin of the skull again till about the 
middle of the marginal. At the place where it articulates the 
slime canal of the marginal reaches the edge of the skull. Be¬ 
hind the postorbital a bone lies between the suborbital and the 
roof of the skull. It overlaps the upper edge of the suborbital 
and is crushed against the skull in such a way that its relations 
can not be determined. It is probably part of the left suborbital 
displaced when the skull was crushed. The posterior end of the 
suborbital lies against the inner part of the anterior projection of 
the clavicular and thus completes the boxing in of the posterior 
part of the skull as well as making the clavicular more rigid. 
The top of the bone is thin and sinuous in outline. The dotted 
lines in figure 2 indicate the parts of the bone that are missing. 
Dinichthys terrelli Newberry. 
Figures 1 and 2. One-fifth natural size. 
1 . 
Median occipital, 
10 . 
Clavicular. 
2 . 
External occipital. 
11 . 
Dorso-median. 
3. 
Central. 
12 . 
Antero-dorso-lateral. 
4. 
Marginal. 
13. 
Post ero-dorso-lat eral. 
5. 
Pineal. 
14. 
Mandible. 
6 . 
Postorbital 
15. 
Postero-supero-gnathal 
7. 
Preorbital. 
16. 
Antero-supero-gnathal. 
8 . 
Rostral. 
17. 
Anterior ventral. 
9. 
Suborbital. 
18. 
Posterior ventral. 
