THE TEMNOSPONDYLOUS AMPHIBIA. 197 



Genus PLATYSTEGOS Dawson, 1895. 

 DAWSON, Proc. and Trans. Roy. Soc. Canada, 1895, xir, p. 77 (sec. iv). 



Type: Platystegos loricatum Dawson. 

 Dawson 's description is as follows: 



"Head broad and short, orbits very large, cranial bones deeply sculptured; teeth 

 strongly plicated and curved, with sharp edges at apices, especially the inner palatal teeth, 

 which are very large. Many minute teeth on the vomerine bones; vertebras ossified, bicon- 

 cave ; limb bones imperfectly ossified, short ; lower surface protected with a thoracic plate 

 and thick, densely imbricated bony scales in transverse rows; body above with thin, round 

 scales, concentrically marked." 



Platystegos loricatum Dawson. 

 DAWSON, Proc. and Trans. Roy. Soc. Canada, xn, p. 77, 1895. 



Dawson describes the species: 



" Head about 8 cm. long; when flattened 9 cm. broad across parietal foramen; squa- 

 mosal and temporal bones projecting backwards in points much behind the condyles; 

 parietal foramen small, orbits large; length of longest tooth seen 7 mm.; cranial bones 

 closely and deeply pitted; humerus with very thin bony walls, cartilaginous within, 3.5 cm. 

 long." 



Erect tree, coal formation, at the South Joggins; collected by P. W. McNaugh- 

 ton. Type in Peter Redpath Museum at McGill University. Dawson regarded 

 the form as of uncertain relationship. 



