1094 



CLASS REPTILIA. 



the paired shields of the plastron were separated by a median series 

 of azygous shields, which probably extended backwards from the in- 

 tergular to the extremity of the xiphiplastral. If the separate bones 

 are rightly interpreted, it would appear that the plastron had a 

 mesoplastral element, which, instead of being situated in the middle 

 of the bony bridge as in Pleuro sternum (fig. 1012), and taking no 

 part in the formation of the axillary notch, formed the anterior part 

 of this bridge and the whole of the notch. The hyoplastral would 

 therefore be entirely above the latter notch, as in the existing Pleu- 



Fk 



1013. — Carapace of Platychelys Obemdorferi ; from the Lower Kimeridgian of Bavaria. 

 One-third natural size. (After Wagner.) 



rodiran genus Sternothcerus. Possibly also a Chelonian, from the 

 Lower Jurassic of Stonesfield, described, upon the evidence of the 

 impressions of the epidermal shields of the carapace, under the 

 name of Testudo Stricklandi, should also find a place in this group. 

 The name Protochelys may be proposed for this form, which has 

 certainly nothing to do with Testudo. 



Section 2. Pleurodira. — The members of this section are, as 

 a rule, characterised by the complete ossification and union of the 

 carapace and plastron, and by the full development of the marginal 

 bones, which are connected with the ribs, as well as by the sutural 

 union or anchylosis (synostosis) of the pelvis with both the carapace 

 and the xiphiplastral part of the plastron. Very frequently the first 



