I.AM) ANIMALS OF THE COAL PERIOD. 357 



rable to the genus Sauropus, to be subsequently mentioned in 



nexion with the discovery of similar footprints in Cape Breton. 

 I have since observed several instances of such impressions at the 

 ;ins, at Horton, and near Windsor, showing that they arc by no 

 paeans rare, and that reptilian animals existed in no inconsiderable 

 Dumbers throughout the coal-field of Nova Scotia, and from the 

 beginning to the end of the Carboniferous period. Two examples are 

 figured- in my " Air-breathers," with those already described. On 

 comparing these with one another, it appears that Logan's, Harding's, 

 and one of mine are of similar general character, and may have 

 been made by one kind of animal, which must have had the fore 

 and hind feet nearly of equal size. The other belongs to a smaller 

 animal, which probably travelled on longer limbs, more in the manner 

 of an ordinary quadruped. Its toes cannot be distinguished. On the 

 whole, these footprints, while differing from those found by Dr King 

 in Pennsylvania, do not prove the existence of any kind of animal 

 distinct from those to be described in the sequel, and known to us by 

 the preservation of portions of their skeletons. 



The study of these footprints shows that the animals which pro- 

 duced them may, in certain circumstances, have left impressions of 

 only two or three of their toes, while in other circumstances all may 

 have left marks ; and that, when wading in deep mud, their footprints 

 were altogether different from those made on hard sand or clay. In 

 some instances the impressions may have been made by animals 

 wading or swimming in water, while in others the rain-marks and 

 sun-cracks afford evidence that the surface was a sub-aerial one. 

 They are chiefly interesting as indicating the wide diffusion and 

 abundance of the creatures producing them, and that they haunted 

 tidal flats and muddy shores, perhaps emerging from the water that 

 they might bask in the sun, or possibly searching for food among the 

 rejectamenta of the sea, or of lagoons and estuaries. 



Mr Brown of Sydney has added to our knowledge of Carboniferous 

 footprints by the discovery of a fine slab, now in the museum of 

 M'Gill University, which indicates the existence of an animal of con- 

 siderable size, the breadth of the "foot being three inches (Fig. 140). 

 The specimen was thus described by the writer in the " Canadian 

 Naturalist:" — 



''The slab exhibits with some distinctness three footprints of the 

 right side, and less distinct traces of the left feet. The feet are short 

 and broad, the fore foot as large as the hind foot, the toes short, broad, 

 and deeply impressed in the sand. Four toes are distinctly marked 

 in both fore and hind feet, and there are indications of a fifth in one 



