TESTTTDINID^. 93 



Homopus comptoni (Bell x ). 

 Syn. Emys comptoni, Bell 2 . 



Shell much depressed, with the areolae of the dorsal shields only 

 slightly impressed. Inner extremities of humero-pectoral sulcus 

 extending horizontally across the plastron. Preaxillary and post- 

 inguinal portions of the plastron short ; xiphiplastrals apparently 

 not notched. 



In the slight areolation of its dorsal shields this species agrees 

 with the existing South- African H. signatus. Its resemblance to 

 that species and H. areolatus was pointed out by its original 

 describer, who seems to have been deterred from referring it to the 

 same genus from the nature of the deposit in which the type 

 specimen was found. 



Hah. Europe (England). 



37210. The shell, wanting most of the marginals, and otherwise 

 {Fig.) imperfect; from the London Clay (Lower Eocene) of the 

 Isle of Sheppey. The type specimen ; figured by Bell in the 

 ' Beptilia of the London Clay, &c.' vol. i. pt. i. pi. xx. The 

 short postero-lateral surfaces of the 1st and 2nd neurals, 

 although not shown in the figure, are distinctly visible ; 

 and the remaining neurals, together with the costals, have 

 the same contour as in the existing forms. The axillary 

 and inguinal buttresses are preserved, and on the right 

 side the axillary one (although not shown in the figure of 

 the anterior aspect) is seen to extend upwards as far as 

 the border of the first costal in the same manner as in 

 existing types. The characters of the plastron are well 

 shown in the plate. Bell Collection. Purchased, 1863. 



Genus STYLEMYS, Leidy 3 . 



Shell with the general characters of Testudo, but with all, or 

 nearly all, the neural bones hexagonal, with short antero-lateral 

 surfaces ; the nuchal not emarginate ; the posterior costals not 

 alternating in length ; epiplastrals not produced, with one notch at 

 the gulo-pectoral sulcus, and the xiphiplastrals not notched. Skull 

 unknown. The caudal shield is undivided. The entoplastral is 

 generally narrow and pointed anteriorly. 



1 Owen and Bell, ' Eeptilia of the London Clay,' &c. (Mon. Pal. Soc), vol. i. 

 pt. i. p. 71 (1849).— Emys. 2 Loc. cit. 



3 Proc. Ac. Nat. Sci. Philad. for 1851, p. 173. 



