28 I 
TESTUDINID. 3 
midline to the lower ends of the peripherals, is about 220 mm. The extreme width of the car- 
apace was about 550 mm. From a line joining the axillary and inguinal notches the bridge 
ascends at an angle of 30°, altho this may have been greater during life. About 130 mm. beyond 
the line mentioned there is an abrupt turn of the carapace upward. This continues, in our 
specimen, to the upper margin of the peripherals, a distance of 135 mm. The abrupt turn men- 
tioned marks the position of a sharp carina which runs along the side of the shell from the free 
border of the carapace in front of the bridge to the free border behind it. Such a carina is seen 
in at least some specimens of H. corsonz. The width of the bridge 1s 250 mm. 
The hinder half of the plastron was very concave, especially from the inguinal notches 
backward. The anterior half was flat. The individual was probably a male. 
The bone of the central portions of the plastron is thin, 17 mm. just behind the ento- 
plastron, in the midline; g mm. at the suture between the hyoplastrals and hypoplastrals; 
and 8 mm.at the anterior end of the xiphiplastrals. 
Near the free borders, however, the bone is very 
thick, 31 mm. at the anterior end of the epiplas- 
tron, 37 mm. at the anterior end of the xiphiplas- 
tron. On the epiplastron the bone is beveled off 
gradually to a sharp edge. Behind the inguinal 
notch the bone is beveled off very abruptly, so 
that the beveled portion is nearly perpendicular. 
The hinder end of the xiphiplastron is 32 mm. 
thick, rough, and with a broad, rounded edge. 
No part of the entoplastron is present, but 
the sutural border of the epiplastron enables us 
to determine something regarding its extent and 
form. It had a breadth of 156 mm. at the hinder 
ends of the epiplastrals. From a line joining 
these it has extended backward about 75 mm. 
From this we may infer that its larger portion lay 
behind the ends of the epiplastrals. It was not 
crost by the humero-pectoral suture. The ante- 
rior end of the hyoplastron, where it articulated 
with the epiplastron, is 55 mm. wide. The extreme 
length of the hyoplastron is 222 mm.; its length 
in the midline is 155 mm. The length of the 
hypoplastron in the midline is 140 mm.; on the 
line joining the axillary and inguinal notches, 173 
mm. At the midline the xiphiplastrals measure 
1r8 mm. At their anterior ends they are 140 mm. 
wide. The notch at the posterior end of the plas- 
tron has not exceeded 25 mm. in depth. 
The suture between the plastron and the per- 
ipheral bones, on the bridge, runs a very sinuous 
course, the opposing bones forming broad inter- 
digitations 35 mm. long. The fifth and sixth 
peripherals are each about 85 mm. wide, fore and aft, and rise about 135 mm. above the turn 
of the carapace upward. 
The plastral buttresses of this species are rather weak, but are relatively better developt 
than in Testudo. They rise to the upper margin of the peripherals. The sulci are deeply 
imprest. The humero-pectoral begins just in front of the axillary notch, runs inward and back- 
ward for a short distance, then straight across the plastron, just missing the hinder border of 
the entoplastron. Behind this sulcus, 55 mm., the pectoro-abdominal sulcus crosses the mid- 
line. It is bent slightly forward on each side, then runs outward, backward, and upward to 
the marginal suture. The abdominal scutes have great extent. Along the midline they measure 
193 mm. The sulcus limiting them posteriorly runs from the midline outward and somewhat 
forward, passing 50 mm. in front of the inguinal notch. The femoral scutes join along the 
Fic. 480.—Hadrianus tumidus.  Plastron, 
lacking epiplastron and entoplastron. 5. 
No. 2090 A. M. N. H 
