EHYNCHOCEPHALIA 



149 



Naosaurus, Cope (Fig. 239). Differs from the last in that the neural 

 spines bear transverse processes. Per- 

 mian ; Texas and Bohemia. 



UmbolopJionis, Thempleura, Arcliaeo- 

 bolus, Li/sorophus, Cojoe. Permian ; 

 Texas. Stereorachis, Gaudry ; Calli- 

 brachion, Boule and Glengeaud. Per- 

 mian ; Autun, France. Known by im- 

 perfect remains apparently allied to 

 Dimetrodon. 



Sub-Order 3. 

 EHYNCHOCEPHALIA VERA. 



Abdominal ribs reduced to three relatively 

 large longitudinal series ; pubis and iscMiivi, 

 well ossified; fifth metatarsal very much 

 shortened, and somewhat expanded. Mar- 

 ginal teeth in one or more uniform series. 



Fig. 240. 



Hyperodapedon gordoni, Huxley. Upper Trias ; 



Elgin, Scotland. A, Superior aspect of skull, i/j- 

 B, Palate. C, Mandibular symphysis from below. 



a, Orbit ; md, Mandibular fork ; mx, Maxilla ; n, 

 Xasal ; pi, Palatine ; /imj;, Preniaxilla ; s, Supra- 

 teniporal vacuity ; s', Lateral temporal vacuity) 

 (after Huxley). ^^ 



Fig. 239. 

 Naosaunts daviger, Cope. Permian; Texas. 

 ■Dorsal vertebrae, anterior and lateral aspects, 1/4 

 (after Cope). 



Family 1. Rhynchosauridae. 



Skull short and broad, with a beak-like 

 rostrum formed by the dowmvardly curved, 

 slender, toothless premaxillae. Mandibles 

 with a swigle, and maxillae and palatines 

 with several longitudinal series of depressed 

 coniccd teeth. External nares confi.uent. 

 Trias. 



Hyperodapedon, Huxley (Fig. 240). Body stout, upwards of 2 m. long. 



