58 Tin: carboniferous. 



the species D. Acadianum; and above this, at the surface of the stump, 

 were some remains and impressions of bones probably indicating 

 another specimen of Dendrerpeton. Taking these specimens in the 

 order above given, we may notice the new facts which they have dis- 

 closed on a preliminary examination. 



2. Remains of Hylerpeton. 



The sole species of this genus heretofore known, //. Dawsoni, was 

 discovered by me in 1860, and was described by Professor Owen from 

 remains so scanty that he expressed considerable doubt as to its 

 affinities. I afterwards worked out, from a few fragments of the 

 matrix, the evidence that its teeth were simple, without plicated den- 

 tine, that it had a large canine or tusk in the anterior part of the 

 upper jaw, and that it possessed a walking foot. The present speci- 

 men throws much additional light on its structure. It had at least 

 twelve teeth in each ramus of the mandible, and they are large in 

 proportion to the size of the animal, bluntly conical and somewhat 

 acuminate, and faintly striate at the apex. The vomei'ine bones are 

 beset with numerous small blunt teeth. The skull is long, and its 

 bones thin and marked merely with delicate incised lines rather than 

 wrinkles. The forms of the stout ribs and scattered vertebras would 

 indicate that the body was broad and squat. The skull must have 

 been about 2 inches in length, the body probably 4 or 5, and 

 there are some small vertebra? which may indicate a short tail. The 

 limbs were large and strong, the femur being an inch and a quarter 

 long, and its shaft a fifth of an inch in diameter, and with thick bony 

 walls. The vertebrae are short and biconcave, and with large dorsal 

 spines, the belly was protected by numerous imbricated bony scabs 

 of two kinds, one oblong and narrow, the other broad and obliquely 

 shield-shaped. There are indications of thoracic plates of larger size 

 than the scales. On the whole, this species was probably a somewhat 

 clumsy creature, of toad-like form and slow gait, and with a dentary 

 apparatus suited to pierce and crush crusts and shells. It is perhaps 

 significant of its habits, in these respects, that the layers of this tree 

 in which its bones occur are alone those in which shells of Pupa 

 vetusta are found. 



The second species of Hylerpeton, which I may provisionally name 

 //. longidentatum, was of somewhat smaller size, with the bones of the 

 skull thinner and more slender, and the teeth very long and 

 sharply pointed, with the apex finely striate, but with no corrugation 

 of the dentine. The vomer is covered with minute teeth, and there 

 are long and slender anterior teeth, resembling canines. The best 



