252 O. C. Marsh—The Wings of Pterodactyles. 
These peculiar features are well ele in Plate III, which 
represents the fossil in the natural s 
The discovery of this Bes bieeieen naturally pa 
much attention at the time, and man 
secure it for Tease museums. The writer was then 
ork on the toothless be haat lag which he had rooniia 
found in the Cretaceous of s, and believing the present — 
specimen important ir his ivetiomiate sent a message by 
cable to a friend in Germany, and lee it forthe museum 
of Yale College, where it is now deposit 
THe Wine MEMBRANES. 
at See eee ee 
A careful examination 4 this fossil shows that the patagium 
of the wings was a thin smooth membrane, very similar to © 
that of modern bats. As “the wings were partially folded at — 
the time of entombment, the volant membranes were naturally — 
contracted into folds, and the surface was also marked by deli- 
cate striz. At first sight, these striz might readily be mis- 
taken for a thin coating of hair, but on closer veers 
they are seen to be minute wrinkles in the su : 
membranes, the ander side of which is exposed. The wing 
membranes appear to have been attached in front along the 
entire length of the arm, and out to the end of the elongated | 
wing finger. From this point, the outer margin curved inward 
and backward, to the hind foot. 
e membrane evidently extended from the hind foot to near 
the base of the tail, but the exact outline of this portion can- 
not at present be determined. It was probably not far from — 
the position assigned it in the restoration attempted in the — 
eut given below, figure 2. The attachment of the inner 
margin of the membrane to the oe was doubtless similar to 
that seen in bats and flying squirre 
In front of the arm, there was fkawins a fold of the skin 
extending probably from near the shoulder to the wrist, as 
indicated in figure 2, This fold enclosed a peculiar bone 
(pteroid), the nature and function of which will be discussed 
below in considering the osteology of this part of the skeleton. 
Tue CaupaL Memprane. 
The greater portion of the tail of this specimen was free, 
and without volant cage nies The distal extremity, how- 
ever, including the last sixteen short vertebrae, supported a 
vertical membrane, which is shown in Plate III, and also in the 
