260 PROCEEDINGS OF THE NATIONAL MUSEUM you, 92 
third the length of the bone. In the type femur this fossa has been 
exaggerated by crushing. The shaft at midlength is nearly circular 
in cross section, and the bone is nearly straight, except toward the 
distal end, where it bends backward. 
The distal articular ‘surface for the most part looks inward at an 
angle of about 30° and backward at about 45°. Of the articular sur- 
face, that part on the inner side for the tibia is much the broader, 
being set off from the fibular portion by a projecting ridge or ccn- 
dyle that turns strongly upward on the posterior face. The fibular 
articulation is principally with the outer side of this condylar pro- 
jection. The intercondylar fossa is relatively shallow. The epi- 
physeal suture of the distal end is plainly visible, as shown in figure 
34, A. 
Measurements of femur of U.S.N.M. No. 15477 (in millimeters) 
Greatestislengths.. 2-2 2. Me See 2 ee 2 i233 
Greatest); width) of proximal end 2222s 288 27 2a 8 22 ee ee ee 22.0 
Greatestawidthof distal end 2222254226 wee ee ee ee 17.8 
east, diameter of Shatt.s2 22 = 2- Seats ee ee ee ee ees Wadi 
Mransyerseudiameter of Neadas Wo ww i ees ee eee ee eee 14.2 
Tibia.—The tibia is about three- 
fourths the length of the femur, with 
a much widened proximal extremity, 
a stout subovate shaft, and a mod- 
erately expanded distal end. In ad- 
dition to the complete right tibia of 
the type (see fig. 35), and the distal 
end of the left, others belonging to 
seven individuals are in the collec- 
tions. In the articulated limb the 
greater diameter of the proximal end 
is nearly anteroposterior in direction. 
The cnemial crest is not prominently 
developed, its outer surface is concave 
and its inner surface 1s convex. The 
Ficure 35.—Right tibia and fibula condyles of this end overhang the pos- 
of Polyglyphanodon sternbergi Gil- terior surface of the bone, more espe- 
more, U.S.N.M. No. 15477, type, aa : . 
a haliatze-« i Gaia ened fon cially the outer one. The distal ar- 
thedronts'B, Abbula,laceral view: ticular end is subovate in outline, with 
a shehtly cupped surface on the outer 
half, slightly convex on the inner. The shaft of the bone is prac- 
tically straight. 
Measurements of right tibia of U.S.N.M. No. 15477 (in millimeters) 
Greatest: lengthy Gece Asse Sie Ls ot ee le A I ea Le 52.9 
Greatest width, of proximal: endent to he eee 19.0 
Greatest wid bh Of sta Teri ge e ase ee eee ee DN ar Vale nae Oe Br gd ak ene ap eT 1B} C: 
Least diameter of shattjatmidlength.2 22205525) Sock ee ed ee wit 5.3 
