410 FOSSIL TURTLES OF NORTH AMERICA. 
project beyond the general border of the lobe. It is truncated in front. The distance between 
the crossings of the gular sulci over the free border is 110 mm. On the upper side (fg. 539), 
the lip extends backward 60 mm., thickening until it reaches 36 mm. There is no excavation 
behind the thickened portion. The suture between the epiplastrals is 65 mm. long. The 
entoplastron 1 is hexagonal, pointed 1 in front, broad behind. The length along the midlinca is 
108 mm.; its greatest breadth is 104 mm. The hinder lobe may be described from Cope’s 
type. In this individual the hinder lobe was 240 mm. wide and 143 mm. long to the ends of 
the xiphiplastral apices. The notch in the rear was about 76 mm. wide and 37 mm. deep. 
In the median portion of this lobe the bone is about 15 mm. thick, but at the inguinal notch 
the thickness is 42 mm. Here the outer face is almost perpendicular, but it at once begins to 
slope inward and upward and to diminish in height, so that at the apices of the xiphiplastra 
the face looks upward and the thickness is only 27 mm. On these apices the face 1s 56 mm. 
wide. From the inguinal notch backward this face is separated from the remainder of the 
bone by a rather sharp ridge. “This markt the boundary between the skin and the bone 
covered with horn. In the case of both the specimens furnishing the posterior lobe there is a 
sharp notch, about 6 mm. deep, at the very apex of the xiphiplastron. 
The gular scutes encroach on theentoplastron. The humero-pectoral sulci pass close behind 
it. The pectoral scutes are about 20 mm. wide at the midline; the abdominals about 75mm.; 
the xiphiplastrals, 50 mm. All of the sulci are narrow, but some are rather deeply imprest. 
A portion of another plastron, No. 1147 (fig. 531), consisting of the left hypoplastron and 
the left xiphiplastron, has a length of 255 mm. The horn-coy ered surface on the apex of the 
xiphiplastron is 74 mm. wide. 
The elements of the right half of the shoulder-girdle are present. The scapula is about 
105 mm. long and 14 mm. wide at the middle of its length. The coracoid is 75 mm. long, 
and its median border is 60 mm. long. The scapula and the procoracoid process make a little 
more than a right angle with each other. 
‘There are in the Meccan Museum of Natural History portions of 2 shells from the same 
region as those described above which are referred with some doubt to the same species. 
They were considerably larger and had thicker bones. Other specimens still, No. 1146 of the 
same museum, collected on Old Woman’s Creek, Wyoming, in White River deposits, may 
belong to T. amphithorax, but the more characteristic parts are missing. The borders of the 
hinder lobe are identical in form with those of the type specimen. 
Testudo quadrata Cope. 
Text-figs. 532, 533. 
Testudo quadratus, Cope, Vert. Vert. Form. West, 1884, p. 764, plate Ixi, fig. 5 —Hay, Bibliog. and Cat. 
Foss. Vert. N. A., 1902, p. 451. 
This species is based on the lip of a plastron and a portion of a nuchal bone. Notwith- 
standing the meager nature of these materials, there can be no question regarding the distinct- 
ness of the species. The remains were collected by Cope in 1873, in the Oreodon beds of the 
White River deposits, at the head of Horse Tail Creek, in northeastern Colorado. The 
individual was evidently a large one. The type specimen is in the American Museum of 
Natural History and bears the number 1149. 
The anterior lip (fig. 532) projected much beyond the general outline of the front lobe. 
The right and left Borders are parallel. “The anterior botder has crumbled away somewhat, 
except at a point near the midline; but it was doubtless truncated, with probably a slight 
notch at the midline. The lateral and probably also the anterior borders were acute. The 
upper surface is slightly convex, the lower nearly flat. Evidently the lip formed something of 
an angle with the ascending lower surface of the plastron. The hinder face of the upper 
part of the lip was not excavated. 
What distinguishes this species from all others of our region is the form of the gular scutes. 
Instead of extending back on the entoplastron, they end at the base of the lip at a sulcus 
which runs at right angles with the midline. Each scute is therefore about square. The 
following are dineneion: of this lip: Length of lip from gulo-humeral sulcus, 70 mm.; width 
of lip at base, 120 mm.; thickness at the base, 29 mm. 
