Sir J. W. Dawson — On Dendrerpeton Acadianum, etc. 147 



Not having visited the Joggins for some years, and the gentleman 

 on whom I had relied to give me intimation of new exposures of 

 reptiliferous trees having left the locality, I made a short excursion 

 to the place last summer, and found two trees partially exposed in the 

 reef. These were extracted with the kindly aid of Mr. McNaughton, 

 Superintendent of the Joggins Mine, but unfortunately proved un- 

 productive. A large tree had fallen from the cliff in the previous 

 winter and had possessed a layer of very productive material in its 

 lower part, much of which had however been removed by the waves. 

 I succeeded in obtaining a portion of tins material, which on examin- 

 ation proved to contain parts of the skeletons of two specimens of 

 Dendrerpeton Acadianum and one of D. Oweni. No other reptilian 

 bones nor remains of millipedes or of land shells were observed. 



The specimens of D. Acadianum were the largest yet found, and 

 some of the bones were in a more perfect state. As examples of 

 these I figure (Fig. 1) the two mandibles of the largest specimen. 

 These seem to have separated on the decay of the body and to have 

 fallen across one another, so that they lie side by side and reversed. 

 They are 8'6 centimetres in length, and one of them shows very well 

 the corrugated sculpture of the bone and a number of the teeth. 

 On the same slab, represented in Fig. 1, is a well-preserved humerus. 

 It has been exposed by cleaning away some of the stone, which 

 probably contains other bones of the fore-leg ; but they cannot be 

 worked out without destroying those in sight. 



Fig. 1. — Humerus and Mandibles of Dendrerpeton Acadianum. j^Tatural size. 



I would call attention to the humerus as indicating the develop- 

 ment of the fore-limb in this species. The bone in this probably 

 mature specimen is better ossified than in smaller and probably 

 younger specimens. In length it is 4-3 centimetres, or half that of 



