4.18 FOSSIL TURTLES OK NORTH AMERICA. 



sulci. It is 58 mm. wide at the base and it narrows slightly toward the tip. The latter is 

 truncated. From its acute free borders the lip thickens rapidly, rising on the upper surface 

 until it attains a thickness of 21 mm. The thickening continues backward 37 mm. from the 

 front. The entoplastron is hexagonal, 49 mm. long and 65 mm. wide at the base. The bridge 

 is 105 mm. wide. 



The hinder lobe is 53 mm. long on the midline, 65 mm. to the hinder ends of the xiphi- 

 plastra. The width at the base is 1 1 1 mm. The notch is 43 mm. wide. At the inguinal notch 

 the free border of the hypoplastron is 22 mm. thick, the outer face rising perpendicularly. 

 Further backward the thickness rapidly diminishes, so that the middle of the free border of 

 the xiphiplastron is acute and thin. 



The gulars occupy 42 mm. of the midline, barely reaching the entoplastron. The numer- 

 als are 55 mm. long, extending slightly behind the entoplastron. The pectorals occupy 15 mm. 

 of the midline. Their outer ends are greatly expanded. The abdominals measure 70 mm. 

 on the midline; the femorals, 25 mm.; the anals, 30 mm. 



Much of the outer surface of both carapace and plastron are sculptured strongly by the 

 lines of growth of the epidermal scutes. 



This species presents the feature, unusual in Testudo, of having only hexagonal neurals. 

 It thus resembles Stylemys; but it differs from the known species of the latter in having a 

 prominent epiplastral lip. 



Testudo farri sp. nov. 

 Plate 69, figs, i, 2; text-figs. 548, 549. 



A species of Testudo was collected in the Deep River formation, of Smith River Valley, 

 central Montana, in 1891, by a party from Princeton University. This specimen has now the 

 catalog number 10486. Only the shell is represented. This has been considerably crusht 

 downward and a little toward the right side. Of the carapace there are missing all behind the 

 fourth neural and the fifth costals, as well as the first three peripherals of each side. The plas- 

 tron is complete. 



While this species resembles in many respects both T. mobrarensis Leidy and T. vaga Hay, 

 it is evidently specifically different from both. 



An estimate, made on comparison with Gopherus polyphemus, indicates that the total 

 length of the carapace (plate 69, fig. I; text-fig. 548) was originally about 310 mm. The width 



was not far from the same. The nuchal 



Dimensions of neurals. i Dimensions oTcortal^tes. bon& is 55 mm ' lon g and 74 mm. wide. The 



first, third, and fifth neurals are 4-sided; the 

 Proximal Distal second, fourth, and probably the sixth are 



:j*k :j*u ' . . 



octagonal. The dimensions of the bones 

 are shown in the table. 



No. Length. Width. 



30 27 



43 



No. 



width. width. 



19 42 



3 35 " 



4 45 



5 Z 9 35 



The costal plates are differentiated, as is 



3 2.6 34 4 18 38 | common in the genus, so that the proximal 



ends are alternately wider and narrower. 

 The table shows the widths. 



The fifth peripheral has a height of 6 1 mm. 

 The upper surface of the carapace is strongly imprest by the lines of growth of the 

 epidermal scutes. The sulci are distinct. The boundaries of the vertebrals are straight lines. 

 The nuchal scute is 15 mm. long and 7 mm. wide. The first vertebral is 54 mm. long, 90 mm. 

 wide in front; the second is 56 mm. long, 55 mm. wide in front, 72 mm. wide at the middle 

 of the length; the third is 55 mm. long, and has a maximum width of 76 mm. 



The plastron (plate 69, fig. 2; text-fig. 549) is 273 mm. long and 203 mm. wide. The 

 front lobe has a length of 70 mm. and a width of 134 mm. at the base. The lip projects 

 only moderately beyond the curve of the lobe behind the gular sulci. Its anterior border is 

 but little convex and appears not to have been notcht. From one gular sulcus to the other 

 the distance is 62 mm. From the front of the entoplastron to the tip of the lip is 23 mm. 

 Lookt at from above, this lip extends backward a distance of 38 mm., then drops off abruptly 

 to the general level of the upper surface of the lobe. The ledge thus formed is deeply exca- 

 vated. The thickness of the bone at the hinder end of the lip is 32 mm. The entoplastron 



