424 O. ©. Marsh—Skull of Pieranodon. 
All these Cretaceous Pterodactyls, so far as known, differ, 
widely from the members of this group in the old world, 
especially in the absence of teeth, and hence have been’ placed 
y the writer in a new order, the Pe lontia, from the 
typical genus, Pteranodon.* Other important characters of 
this order have since been made known by the writer, showing 
that these strange reptiles constitute a well marked group, 
much more specialized than any hitherto discovered. 
n the present paper, the skull of one species of Pteranodon 
is described and figured as typical of the order, and the 
remaining part of the skeleton will be discussed in subsequent 
communications. 
THE SKULL. 
The skull in the genus Pteranodon is very large, and much 
elongated. e facial portion is greatly produced forwards, 
and an enormous sagittal crest extends far backward, and 
_ somewhat upward, as shown in Plate XV, figures 1, 2, and 3. 
Seen from the side, the jaws project forward like a huge pair — 
of pointed shears. They are very long, sharply pointed in 
The bones of the skull are nearly all of extreme tenuity. 
With the exception of the occipital condyle, and the lower 
ends of the quadrates, all seem to have been pneumatic. 
Seen from above, the skull appears extremely narrow. A 
sharp ridge extends from the end of the premaxillaries alone 
the median line to the true cranium, and is continued backwar 
by the thin elevated crest. The large antorbital openings thus 
seem near the middle of the skull, and, as they are directly 
* This Journal, p- 507, vol. xi, June, 1876; p. 479, vol. xii, Dec., 1876, 
, and vol. xxi, p. 342, April, 1881. See also vol. xxiii, p. 251, April, 1882. 
