1853.J OWEN BRITISH CARBONIFEROUS REPTILE. ^^ 



ance of rays ; but this appearance seems to be due to the abrasion or 

 removal of the very thin parts of the bone impressed by the grooves, 

 the thicker raised interspaces being left. 



No. 9 shows the half-twist characteristic of the bone (lower or distal 

 element of the ilium) alluded to by Dr. Wyman (see above, p. 65, 

 No. 5), which character, however, is manifested by most of the long 

 bones of the Menopoma. In reference, however, to the bone in the 

 hyoid arch of Ganoid fishes, to which this and other of the long bones 

 in the fossil in question have been compared, I would remark, that the 

 half-twisted character is not present in the cerato-hyal, or other element 

 of the hyoid apparatus, in the Lepidosteus, approaching in shape to 

 any of the long bones of the fossil : and I would further remark, 

 that the sum of the evidences afforded by the several remains agrees 

 best with the characters derived from the skeletons of the perenni- 

 branchiate Batrachians. Although a single bone, amongst the series 

 obtained from the Nova-Scotian coal-tree, may show some resemblance 

 to the cerato-hyal of a Lepidosteus or Amia, the characters of all the 

 other fossil bones accord closer with those of the above-cited batra- 

 chian skeletons, and do not repeat the characters of any bone in the 

 known existing ganoid and salamandroid fishes. Had the fossil bones 

 found in the coal-tree belonged to a ganoid fish, although one pair 

 — the cerato-hyals — might have resembled certain long bones of a 

 batrachian, those of the rest of the skeleton would have offered un- 

 mistakeable piscine characters, whilst these are not shown by any of 

 the bones extracted from the coal-tree. 



P.S. [March 9, 1853.] — Although the long bones have been com- 

 pared by Dr. Wyman and myself to those in the skeletons of existing 

 Perennibranchians, it is not improbable that the corresponding bones 

 in the Archegosaurus and Labyrinthodon would present similar cor- 

 respondences : and the sculptured surface of No. 4 (PI. II. fig. 5) offers 

 significant evidence of the closer aflfinity of the Nova-Scotian coal-field 

 reptile to those that have been discovered in formations of correspond- 

 ing age in Europe. The reptile or batrachian in question cannot be re- 

 ferred to any known species of Archegosaurus or Labyrinthodon ; and, 

 it having been suggested that it would be convenient to the geologist 

 to have a provisional name for this fossil, that of Dendrerpeton Aca- 

 dianum is proposed : the generic name having reference to the peculiar 

 circumstances under which the fossil reptile was found, and the specific 

 name indicating the geographical position of the coal-field, — Acadia 

 being the ancient Indian name of Nova Scotia. 



2. Notice of a Batrachoid Fossil in British Coal-shale. 

 By Professor Owen, F.R.S., G.S. &c. 



[Plate II.] 



Whilst in the museum of the Earl of Enniskillen, during a visit at 

 Florence Court, after the Belfast Meeting of the British dissociation, 

 September 1852, my attention was called by Prof. M'Coy to a coal- 

 shale fossil in a drawer of unnamed and unarranged specimens, 



