8a 



THE COAL MEASURES AMPHIBIA OF NORTH AMERICA. 



An additional species of this genus was apparently indicated by some fragmen- 

 tary remains, but Dawson thought best not to describe them as such, since they 

 might indicate only a young individual of the present species. 



Ix;ngth of mandible 1.5 cm. 



Length of femur 1 .5 cm. 



Length of humerus (?) 1.3 cm. 



Length of vertebra 3.5 mm. 



Length of rib i cm. 



There are 5 teeth in 2 mm. 



FiG. 1 8. — Skeletal elements of Smilcrpelon aciedentatum Dawson, from the Coal Measures 

 of Nova Scotia. (After Dawson.) a, shaft of femur? X 2; i, intermaxillary and teeth, 

 X 25; c, sections of teeth, X 25; d and e, palatal teeth, X 25;/, femur, X 2; g, rib, 

 X 2; A, palate; », caudal vertebra;; j, long palatal tooth, X 25; ^, bony scale. 



Genus HYLERPETON Owen. 



Owen, Quart. Jour. Geol. Soc. London, xviu, p. 241, 1862. 



Dawson, Amcr. Jour. Sci. (3), xii, p. 443, 1876. 



Dawson, Phil. Trans. Roy. Soc. London, 1882, pt. 11, p. 634. 



Dawson, Proc. and Trans. Roy. Soc. Canada, 1895, p. 74. 



Dawson, Air-breathers of the Coal Period, p. 55, pi. vi, figs. 32-46, 1863. 



Body stout, with strong limbs. Mandibular and maxillarj' teeth strong, 

 not numerous, grooved at apex. Palatal teeth numerous, and some of them large. 

 Thoracic plate broad. Abdominal scales pointed or oat-shaped: 



Type: Hylerpeton dawsoni Owen. 



Hylerpeton dawsoni Owen. 



Owen, Quart. Jour. Geol. Soc., xvni, p. 241. 



Dawson, Air-breathers of the Coal Period, p. 55, 1863. 



Dawson, Acadian Geology, p. 380. 



Dawson, Phil. Trans. Roy. Soc. London, 1882, pt. 11, p. 639, pi. 41, figs. 62-85. 



Dawson, Proc. and Trans. Roy. Soc. Canada, 1894, xii, p. 74. 



Type: Specimen No. 3061-4, Peter Redpath Museum, McGill University. 

 There are also specimens, Nos. R 441 and 442, in the British Museum (393, pt. iv, 

 p. 225). (Plate 7.) 



Horizon and locality : Coal formation at the South Joggins, Nova Scotia. 



Bones of skull slightly striated, but not sculptured as in Dendrerpeton. Lower 

 jaw with distinct ascending ramus or coronoid process, a feature not known in any 

 other of the Nova Scotia fauna, but observed by Cope in Brachydectes. Teeth, 12 

 in each ramus of the mandible, bluntly conical, slightly striated at the apex. , Pulp- 

 cavities large and longitudinally striated at the sides, though the teeth are not 



