230 FOSSIL TURTLES OF NORTH AMERICA. 
some portions of the neurals and the contiguous borders of the ght third and fourth costal 
plates are wanting. 
The carapace (plate 33; text-fg. 288) is deprest, due probably in some degree to pressure. 
The anterior border is excavated over the neck, broadly rounded behind. Behind the ingui- 
nal notches the borders are somewhat flared upward. 
The length of the carapace from the bottom of the notch in front to the rear, measured in 
a straight line, is 715 mm.; the breadth is very close to 585 mm. The anterior notch is 22 mm. 
deep. The free border in this notch is about 25 mm. thick. On each side of the midline the 
border thins rapidly and soon forms an acute edge, which continues to the axillary notch. 
Behind the inguinal notches the free edges are acute. 
The nuchal bone measures 85 mm. along the midline; its width is 145 mm. The first 
neural was about 80 mm. long and 60 mm. wide behind. The second neural is oval, 68 mm. 
long, 40 mm. wide. The third is broadest in front, 80 mm. long, 50 mm. wide. The fourth 
neural is wanting; the fifth 1s defective. The sixth is 70 mm. long, 50 mm. wide. The seventh 
and eighth are small and irregular in form. There is a small first suprapygal. The second 
is bifurcate, as in Testudo. It measures along the midline 60 mm.; its lateral extent is 170 
mm. The third suprapygal is 72 mm. along the midline and 135 
mm. wide. The pygal bone is 52 mm. high and 75 mm. wide. 
The tenth peripheral bone is 85 mm. along the free border and 
102 mm. high. There are 11 pairs of peripherals. 
Vertebral. Length. Width. 
z 190 se The nuchal scute is small, about 25 mm. long and 15 mm. 
2 145 100 o = . . 
z sae 168 wide. The first vertebral scute is unsymmetrical. On the left 
4 125 go side the anterior border extends 100 mm. from the midline; on the 
3) 140 235 
right side apparently only 60 mm. The left appears to be the nor- 
mal side. The table herewith gives dimensions of the vertebrals. 
It will be observed that, with the exception of the first and the last, the vertebrals are 
considerably longer than wide. The costal scutes are large. The second has a longitudinal 
extent of 160 mm. and a height of 240 mm. They extend far below the costo-peripheral 
sutures. Of the marginal scutes there are 12 pairs. The second extends from the free border 
42 mm. to the first vertebral scute. The third has a height of 60 mm.; the ninth a height of 
60 mm.; the twelfth, a height of 75 mm. 
On the lower side of the first and second peripherals the portion covered by the horny 
scutes is about 50 mm. wide. Toward the nuchal bone and the axillary notch this narrows 
greatly. Behind the inguinal notches the horn-covered surface on the lower side of the periph- 
erals is about 45 mm. wide to the midline behind. 
The plastron (plate 33; text-fig. 289) has a total length of 660 mm. The lobes are short, 
the bridges wide. The length of the anterior lobe, to a line joining the bottoms of the axillary 
notches, is 160 mm. The breadth, taken from the inner border of one axillary notch to the 
other, is 330 mm. 
Anteriorly the lobe ends in a beak as prominent as that of many species of Testudo. 
From the anterior end of one gulo-humeral sulcus to the other, the width is 95 mm. The beak 
extends 42 mm. in front of this. On the lower surface the beak is nearly flat, but toward the 
front it develops a broad median channel. Laterally the borders of the beak, like those of 
the whole anterior lobe, are subacute. From this subacute edge the bone rises abruptly and 
nearly perpendicularly, finally rounding off into the convex upper surface of the beak. The 
maximum thickness of the bone is 50 mm. On the upper side of the beak the ornamented 
surface extends back about 55 mm. From the sides of the beak this sculptured surface narrows 
toward the axillary notch. At the junction of the epiplastron with the hyoplastron the bone 
is 35 mm. thick. The median portions of the anterior lobe are much thinner. 
The entoplastron is short but very wide. Its fore-and-aft extent is 110 mm., the breadth, 
145 mm. The form is shown in the figures. 
The bridges are about 370 mm. wide. The hinder lobe has a length of 145 mm. and a 
width of 300 mm. At the borders, for some distance behind the inguinal notches, the bone 
turns abruptly and perpendicularly upward to the summit of a ridge running backward from 
the inguinal notch. From the summit of this ridge the bone slopes rapidly downward to the 
central portion of the lobe. At the hypoxiphiplastral suture the ridge is 50 mm. above the 
a 
