1072 



CLASS REPTILIA. 



diverged posteriorly, or gave off wings uniting in the middle line 

 upon the basi- and presphenoid, and thus completely closing the 

 posterior portion of the palate (fig. 991) — an approximation to the 

 latter arrangement occurring in some Chelonia. The palate was 

 also devoid of infraorbital vacuities. The coracoids (fig. 987) had 

 a short median symphysis, not extending as far forwards as the 

 scapular articulation, and also had a groove ; while the ventral 

 plates of the scapulae were very small. Typically, the cervical 

 vertebrae have double costal facets, while the transverse processes 

 of the dorsals are very short, and remarkable for the vertical elonga- 

 tion of their articular faces. The humerus and femur are elongated 

 — the former (fig. 993) having an entepicondylar foramen, but no 

 distinct distal expansion. The ischium and pubis did not unite to 

 enclose an obturator foramen. 



The known forms occur typically in the Muschelkalk, or Middle 

 Trias, of the Continent, but some of them range up into the 

 overlying Keuper, and one species is found in the Bunter, or 

 Lower Trias. In the typical genus Nothosaurus the skull (figs. 

 991, 992) is long and much depressed, the length of the post- 

 orbital exceeding that of the preorbital portion. The characters 



Fig. 992. — Right lateral aspect of the skull of Nothosaurus 

 mirabilis. Reduced. (After Meyer.) 



Fig. 993. — Ventral as- 

 pect of the right humerus 

 of Conchiosaurus. One- 

 half natural size. Entf, 

 Entepicondylar foramen ; 

 a, Ectepicondylar groove. 



of the palate are shown in fig. 991. Co?ichiosanrus is a closely 

 allied but smaller form, in which the teeth are club-shaped. In 

 Simosaurus the skull is characterised by the breadth of the facial 

 portion and its stout teeth. The type species is nearly equal in 

 dimensions to the larger species of Nothosaurus. Finally, Pisto- 



