THE 



GEOLOGICAL MAGAZINE. 



NEW SERIES. DECADE III. VOL. Vlil. 



No. IV.— APRIL, 1891. 



Oiei<3-IZsr.A.Xj .A.I2,TIOXjES. 



I. — On New Specimens of jDendrerpeton Acadianum, with 

 Remarks on other Carboniferous Amphibians. 



By Sir J. William Dawson, LL.D., F.R.S., etc. 



THE genus Dendrerpeton was established by Owen on the evidence 

 of remains found by Sir C. Lyell and the writer in an erect 

 tree at the South Joggins in Nova Scotia in 1852.' Other speci- 

 mens were afterwards obtained, and the most complete, presented 

 by me to the Cabinet of the Geological Society, was found in 1861, 

 and described in my *' Airbreathers of the Coal Period." ^ These 

 remains rendered it certain that the animal belongs to the order 

 Labyrinthodontia,^ and it is regarded by Lydekker as the type of 

 a family in that group.* 



As the characters of the type-species ascertained by Owen and by 

 the writer have not as yet been stated in connected form, and the 

 genus may in consequence be said to be still imperfectly known, it 

 may be useful to sum them up before proceeding to notice some 

 specimens recently obtained, and which have added somewhat to 

 our knowledge of the type-species. 



Dendrerpeton Acadianum, Owen, Journ. Geol. Soc. Lond. vol. ix. 1853. 



Skull of moderate size and rounded broadly in front. Nostrils 

 small and near the muzzle. Orbits nearly in the middle of the 

 length. Occipital condyle double. Parietal foramen small. Sur- 

 face of cranial bones sculptured with relatively deep pits. Teeth 

 conical, smooth above, grooved at base, especially on the inner side ; 

 enamel simply plicated at base. Outer series of teeth somewhat 

 unequal and larger anteriorly in the intermaxillary bones. A few 

 large teeth within on the inner surface of the maxillaries. A group 

 of small simple teeth on the vomerine bones. Mandibles sculj)tured 

 like the skull, but much more feebly. Teeth similar to those in the 

 upper jaw, but not larger in front. For the arrangement of the 

 central cranial bones see diagram in Memoirs on Animal Remains 

 in Erect Trees, Phil. Trans. Royal Society, 1882, pi. M. 



1 Journ. Geol. Soc. of London, vol. ix. p. 66. A preliminary examination of the 

 specimens had been made by the late Prof. J. "Wyman, of Cambridge, U.S., and 

 "was quoted by Prof. Owen. 



^ Montreal, 1863. See also Journ. Geol. Soc. vol. xvi. p. 273 ; vol. xviii. p. 5 ; 

 and vol. xix. p. 470. 



^ Journ. Geol. Soc. vol. xv. p. 274 ; also " Airbreathers of the Coal Period." 



* Brit. Museum Catalogue, Eep tiles and Amphibia, vol. iv. p. 170 ; also 

 Nicholson and Lydekker, Manual of Palaeontology, vol. ii. p. 1032. 



decade III. — VOL. VIII. — NO. IV. 10 



