22 PROCEEDINGS OF THE NATIONAL MUSEUM. volxxii. 



of the costals are alteruately very wide and very narrow. In Hadri- 

 antis the elements of the carapace have not attained such differentiation. 

 The species here described is named in honor of its discoverer. It 

 will therefore be known as 



HADRIANUS SCHUCHERTI. 



The total length of the shell of this tortoise was originally close to 

 75 cm. (30 inches) ; its width, 52.5 cm. (21 inches). As will be seen from 

 an inspection of Plate lY, the lateral borders of the shell are nearly 

 straight, and parallel with each other. In front of the forelegs the 

 margins round rapidly into the anterior border, so that in front the 

 carapace is quite truncate. The hinder border approaches a segment 

 of a circle. ]S"either the anterior nor the posterior margin is to any 

 degree serrated. 



The marginals rise on the side of the carapace to a height of 10 cm. 

 The passage from the lower surface of the shell to the upper is quite 

 abrupt; but this is due to a considerable extent, at least, to distortion 

 from pressure. In living forms of Testudo the upper portion of the 

 shell usually rounds gradually into the lower portion. 



The borders of the carapace over the openings for the posterior limbs 

 are gently reverted ; over the openings for the lower limbs the carapace 

 is somewhat more strongly reverted. The caudal marginal appears to 

 have descended without any upward Hare. 



The plastron is concave; it has a length of 67.5 cm. On a line 25 

 mm. in front of the axillary notch the width of the anterior lobe of the 

 plastron is 28 cm. The tip of the lobe is prolonged into an obtuse angle. 

 The tip is considerably thickened in front, but the borders are rather 

 acute. The tip of the lobe was not prolonged in front of the carapace. 

 In Hadrianus octonarius, the type of the genus, the plastron ends in 

 front in a very broad and truncate lip. 



The width of the bridge is slightly more than one-third the length of 

 the plastron. Measured on a line 25 mm. behind the inguinal notches, 

 tlie width of the hinder lobe of the i)lastron is 30 cm. This lobe is 

 deeply notched on its hinder border. The posterior angles may, how- 

 ever, have been somewhat more rounded than in the restoration. 



The entoplastron has a width of 15 cm. Its hinder border can not 

 be accurately traced, hnt its position was not greatly different from 

 that represented by the dotted line on Plate V. The other bony ele- 

 ments of the plastron have their boundaries shown on the same plate 

 by means of the continuous zigzag lines. They present no essential 

 variations in form or position from those of modern species of Testudo. 



The conformation of the epidermal scutes, whose sutures are shown 

 by the stippled lines in Plate Y, is not, so far as can be determined with 

 certainty, essentially different from that of the shields of recent species 

 of Testudo. The gulars did not encroach on the territory of the ento- 

 plastron. The humero-pectoral suture runs straight across the plastron 

 until it approaches the axillary notch, when it turns abruptly forward. 



