TESTUDO. 111 
The sternum appears to have been quite flat, and the axillary and inguinal 
notches are directed downward. 
Plates of the Carapace-—(Pl. XXIII. 1.) The first vertebral plate has convex 
sides, and has the form of a sugar-loaf; it is two and three-quarter inches long and 
one inch seven lines broad at its middle. 
The second and third, and portions of the fourth and seventh, and the eighth 
vertebral plates, preserved in the specimen, are hexahedral, and the first two are 
subequal. 
The ninth, or inverted V-shaped vertebral plate, is a little depressed anteriorly to 
receive the border of the plate in advance. 
The tenth, or rhomboidal vertebral plate, is two and three-quarter inches long, 
and three and a half broad. 
The first costal plate is six and three-quarter inches wide and four and a half 
inches antero-posteriorly, and articulates with the first to the third marginal plates 
inclusive. 
The nuchal plate, as in all the species described, reaches only the anterior angle 
of the position of the first costal scute, and there measures seven inches in breadth. 
Plates of the Plastron—(P\. XXIII. 2.) The entosternal plate is pyriform, and 
is four inches long and three-fourths of an inch broader. 
The hyosternal plates are seven and a quarter inches long, and articulate with 
the marginal plates from the third to the middle of the sixth inclusive. 
The hyposternal plates are five and a half inches long, and articulate with the 
sixth and seventh marginal plates. 
The xiphisternal plates, where in contact, measure four inches in length. 
Scutes of the Carapace.—(Pl. XXIII. 1.) The second vertebral scute is quadri- 
lateral, and is four inches long and three-fourths of an inch greater in its breadth. 
The lateral margins are slightly bow-formed and parallel, and the anterior and 
posterior borders are concave. 
The last vertebral scute is prolonged anteriorly into a cup-shaped process, 
receiving the scute in advance. 
Scutes of the Plastron.—(P\. XXIII. 2.) The gular scutes are angular posteriorly, 
and encroach for one inch upon the position of the entosternal plate. 
The humeral scutes are one and a quarter inch long internally, and outwardly 
join the axillary and the fourth to the middle of the sixth marginal scute. 
The abdominal scutes are five and a half inches long, and join the sixth and 
seventh marginal and the inguinal scutes. 
MEASUREMENTS. 
Inches. 
Estimated length of the sternum : ; ; ; ; : : : . 21 
Breadth of the sternum. 3 : : ; é : : c : : 15 
Estimated length of antero-posterior curve of the carapace. 5 s : : 27 
Estimated length of transverse curve . A : ; 3 : : AY 27 
Height above level of the sternum. : : : : : : : , 8 
Length of lateral marginal plates : f . : : ; . 4 5 
