WILLISTON: RESTORATION OF ORNITHOSTOMA (PTERANODON). 47 
of these fingers are of two kinds. The proximal ones are elon- 
gate, with a contracted shaft, about an inch and a quarter in 
length, with the proximal end concave and the distal convex with 
a median depression. ‘The others are but little longer than broad, 
with similar articular surfaces. The ungual phalanges are broad, 
and strongly curved, terminating in a sharp point, and much re 
sembling the claws of carnivores. The proximal end has the artic- 
ular surface on the upper half only. 
The fifth metacarpal is much broader at the base, gradually 
diminishing in size to near the distal extremity, where the bone 
must have been subcylindrical in section with the under surface 
flattened or grooved. Proximally the bone appears to have had a 
gentle convexity on the proximal end and a corresponding concav- 
ity on the under side. The articular surface for the carpal is 
large, with the dorsal border somewhat produced for muscular in- 
Sertion. The distal extremity is placed somewhat obliquely to the 
Shaft, being directed downward and forwards. The articulation is 
a very complete pulley-shaped mass, permitting motion through 
nearly half a circle. The posterior condyle extends through more 
than three-fifths of a circle, with its lower border directed forward 
and projecting beyond the anterior surface of the shaft, permitting 
the corresponding articulation of the first phalange to overlap the 
shaft to a considerable extent. The anterior condyle extends 
through a lesser are and does not project beyond the surface of the 
bone, the corresponding articulation of the phalange being shorter. 
The articular surface is deeply grooved, the groove being before 
the middle, the broader surface belonging to the posterior condyle. 
The inferior surface of the shaft distally is concave, and behind the 
Proximal ends of the articular surfaces there isa pneumatic for 
amen, 
Measurements of wing metacarpal: 
PERCE REIN io ie aig CONIA e Lal Key Ae MOO: oR yor Bd «cs eens 
Wadthnat promimeal "endive hei iia 98 70 70 70 
Diameter of shaft before condyle.. 32 30 28 32 
Diameter of anterior condyle..... 36 35 BA HO 
First Phalange. 
The first phalange of the wing-finger is the longest bone in the 
body.. On the proximal end the shaft is expanded, but beyond the 
Proximal fifth the sides of the bone are nearly parallel and straight 
to near the tip, where the whole bone is bent downward. The 
Proximal articular surface is deeply concave in ontline, the chord 
