TESTTTDINID.^. 71 



Family TESTUDINIDiE. 



Ossification of shell complete ; plastron connected with the cara- 

 pace either by suture or a straight ligamentous junction ; nuchal 

 bone without distinct costiform processes; carapace more or less 

 ovoid, and covered with epidermal shields. Caudal vertebrae pro- 

 coelous. Skull with open temporal fossa ; tympanic ring formed solely 

 by quadrate ; tympanic cavity closed posteriorly ; bones of palate de- 

 veloping longer or shorter palatal plates to floor the narial passage. 

 Scapula and precoracoid generally forming an obtuse angle at their 

 junction; humerus more or less strongly curved, with the axis of 

 the head widely removed from that of the shaft, and the radial 

 process large and reaching above the level of the head (fig. 1, C). 

 Pubis and ischium uniting to form an obturator foramen. Limbs 

 with free digits, which are short or of moderate length ; phalangeals 

 with condyles ; and the terminal claws either four or five in number. 

 Both inframarginal and intergular shields are wanting. 



This family is taken to include the Oistudinidce and most of the 

 Emydidce of Gray. 



Genus TESTUDO, Linn. » 



Including Colossochelys, Falconer and Oautley 2 . 

 Manouria, Gray 3 . 



Neural bones short, and usually comprising an alternation ot 

 smaller tetragonal and larger octagonal ones (fig. 12), but occasionally 

 hexagonal with short postero-lateral surfaces; costals alternately 

 short and long at their inner and outer extremities ; nuchal deeply 

 emarginate. Suture between costal and marginal bones usually 

 coincident with the sulcus between the corresponding shields ; caudal 

 shield usually single, but in some cases divided. Plastron extensively 

 united with the carapace by suture, with short buttresses, which 

 never extend beyond the edges of the costals ; entoplastral usually 

 anterior to the humero-pectoral sulcus; extremity of epiplastrals much 

 thickened, and more or less distinctly produced anteriorly, so as to 

 form a notch at gulo-pectoral sulcus ; xiphiplastrals notched. Verte- 

 bral shields broad ; pectorals very short. Skull with one or two ridges 

 on oral surface of palate, and the pterygoids unusually wide, and 

 much depressed in the middle line. Humerus (fig. 1, C) greatly 

 curved, with the radial and ulnar processes approximated on the 

 ventral aspect. Coracoid short and much expanded distally. 



The entoplastral is usually broad, and not narrowed anteriorly. 

 The heads of the ribs are aborted. 



1 Syst. Nat. ed. 6, Vol. i. p. 350 (1766). 



2 Proc. Zool. Soc. 1844, p. 54.— As a subgenus. 3 Ibid. 1852, p. 133. 



