No. 446.] RECLASSIFICATION OF THE REP TI LI A. 105 



IV. Order Testudinata (o' Shaw.) 



The kinship of the Testudinata to the Synapsida is indicated 

 both by the skull structure and by the phalangeal formula. The 

 shoulder girdle structure, like that of the plesiosaurs, is still in 

 dispute ; the main question being as to the homologies of the 



tepicondylar 



itral processes variously known as the " procoracoid ' 



SUBCLASS DIAPSIDA Osborn. 

 All these animals are readily distinguished by their general like- 

 ness to the existing Hatteria. In contrast to the Synaps.da he 

 cranium is short ; the temporal region is primitively fenestrated 

 by two distinct openings, the supra- and latero-temporal fenestra, 



