TKSTUDINID^E. 4OI 



That which distinguishes this species from those of the genus Stylemys is the prominent 

 epiplastral lip (plate 66, fig. 1). How long this was originally it is now impossible to say, 

 for the anterior end has been broken awav. The portion remaining extends 32 mm. beyond a 

 line joining the anterior ends of the gulo-humeral sulci. The thickness of the broken end is 

 26 mm. It appears probable therefore that the lip was at least 60 mm. long. Its width at the 

 base is 80 mm. The lower and upper faces are convex from side to side. The free edges are 

 acute, as are also the epiplastral edges behind the lip. Opposite the anterior ends of the gulo- 

 humeral sulci the thickness of the lip is 32 mm. Seen from below, the plastron rises toward the 

 lip, so that the latter projects on a slightly higher plane. Seen from the upper side, the lip is 

 carried backward 20 mm. behind the line joining the anterior ends of the gulo-humeral sulci. 

 It attains a thickness of 35 mm., then slopes off rapidly to the entoplastron. 



The entoplastron has a length of 93 mm. along the midline and a width of 107 mm. Its 

 form is approximately rhomboidal. 



The gular scutes extend on the entoplastral bone. The sulci are deeply imprest. Altho 

 the plastron is present at the midline a distance of 40 mm. behind the hinder border of the ento- 

 plastron, there is no certain trace oi the humero-pectoral sulcus. 



The skull is in a good state of preservation. The premaxilla? are missing, as are most of 

 the right maxilla, the tip of the left dentary, and the anterior half of the right dentary. 



The length of the skull (plate 66, figs. 2-4) from the upper border of the nasal opening to 

 the occipital condyle is 85 mm. The breadth just in front of the tympanic cavities is 62 mm.; 

 between the outer borders of the articulation of the lower jaw, 60 mm. In front of the temporal 

 fossae the upper surface of the skull is quite flat. Seen from the side the upper surface of the 

 skull is nearly straight from the snout to the end of the supraoccipital. The interorbital space 

 is 23 mm. wide. The jugal arch has a height of 13 mm.; the postorbital arch a width of 10 mm. 

 The frontals furnisht a small portion of the rim of the orbit. The antero-posterior diameter 

 of the orbit is 24 mm.; the perpendicular diameter, 18 mm. The roof of the mouth is moder- 

 ately vaulted, and is traverst along the midline by a sharp ridge. The triturating surface of the 

 upper jaw has a longitudinal rough ridge and a less conspicuous inner ridge. Posteriorly the 

 palate is reduced to a width of 13 mm. 



The dentary bone (plate 66, fig. 5) is channeled from the coronoid process to near the 

 symphysis, to receive the dentated ridge of the upper jaw. The lower jaw is 19 mm. high at the 

 coronoid process. 



The distal half of the left humerus is present. The width of the distal end is 54 mm. The 

 left radius has an extreme length of 92 mm. A claw phalange has a length of 20 mm. and a 

 width of 16 mm. 



The cervical vertebrae are more or less damaged. One has the centrum 40 mm. long. 



This was a large turtle, the length of the carapace being estimated at about 625 mm. 



Thru the kindness of Dr. S. W. Williston, of the University of Chicago, the writer has 

 been permitted to examine a testudinid skull which was collected in 1894 by Dr. George Baur. 

 It was obtained in the same locality as the specimen above described and probably in the same 

 beds. The skull is somewhat fragmentary and lacks the symphyses of the upper and lower 

 jaws. It appears to have belonged to T . thomsom, but it presents some differences. The orbit 

 is more nearly circular than in the type; but the type may have suffered some distortion in this 

 region. The upper longitudinal outline of the skull of Dr. Baur's specimen is not so straight, 

 the supraoccipital crest not rising so high. The skull is that of a smaller specimen and the 

 depression of the crest may be due to an earlier stage of growth, to sex, or to individual 

 variation. 



Testudo exornata Lambe. 



Plate 66, figs. 6, 7; text-figs. 506-508. 

 Testudo exornata, Lambe, The Ottawa Naturalist, xix, 1906, p. 187, plate iii, figs. 1-3. 



All the know n specimens of the present species belong to the Geological Survey of Canada. 

 They consist wholly of fragments of costal plates, which were collected in 1904, by Mr. Law- 

 rence M. Lambe, vertebrate paleontologist of the Canadian Survey, in the Oligocene beds of 



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