DERMATEJMYDID^E. 131 



vol. vi. art. 1, p. 56, pi. viii. fig. 2, and also by Pictet in 

 his ' Paleontologie Suisse : Cheloniens de la Molasse,' 

 pi. xxi. fig. 3. The specimen is described by Meyer as 

 the third or fifth costal of the left side ; but it would ap- 

 pear to be a late right costal. It shows the outer sulcus 

 of a vertebral shield, which forms a distinct V, and the 

 proximal part of a sulcus between two of the costal 

 shields. The neural shields were evidently of consider- 

 able width. 

 Brown Collection. Presented by Sir 11. Owen, K.C.B., 1860. 



r 



Trachyaspis hantoniensis, Lydekker 1 . 



There is at present no decisive evidence to show whether this 

 rm is distinct from the preceding, although its much lower horizon 

 would indicate the probability that this is the case. 

 Hob. Europe (England). 



R. 1443. The nearly entire penultimate marginal of the left side ; 

 from the Upper Eocene (Lower Oligocene) of Hordwell, 

 Hampshire. The type. The upper and lower borders 

 are somewhat broken ; the extremity of the sulcus of the 

 eighth costal shield is shown, and also that between the 

 antepenultimate and penultimate marginal shields, both 

 having the same arrangement as in Dermatemys. Part of 

 the pit for the rib also remains ; in its curvature the spe- 

 cimen agrees with the hinder marginals of T. cegyptiaca. 



No history. 



Trachyaspis segyptiaca, Lydekker 2 . 



Carapace depressed and ovoid, with a median and a pair of costal 

 keels. Yertebral shields long and narrow, their lateral portion only 

 extending a short distance on to the costals, and not forming a 

 distinct Y. Sculpture finer than in the type species. Eive costal 

 shields. 



Hob. Egypt. 



R. 229. The imperfect carapace, with the inner cavity filled with 



{Fig.) matrix ; found in beds of unknown Tertiary age during 



the digging of the Suez canal. The type ; figured in the 



woodcut on the next page. Except on the right side the 



margin is imperfect, and a considerable portion of the 



1 Ann. Mag. Nat. Hist, ser. 6, vol. iii. p. 54 (1889). 



2 Ibid. p. 53 (1889). 



k2 



