198 Dr DUNCAN on the Foot-marks of Quadrttpeds 



Breadth of the impressions across the toes, 1|- inch. 



Length of the step, as above explained *, 8 



Distance directly across between the line of 

 the right and left foot-marks behind and 

 before, about - 3 



Distance from the claws of the hind-foot to 

 those of the nearest mark of the fore-foot, 

 about - 2 



In both of the specimens already mentioned, the track of the 

 animal was in an upward direction, that is, from the bottom to the 

 top of the quarry, almost in a direct line, along a smooth surface, 

 inclining like the rest of the strata of the sandstone at an angle of 

 38. This at least I can aver, from personal observation, to have 

 been the case with No. 2, which I saw removed from its original 

 bed. The track continued along the whole face of the flag as it 

 lay in the quarry till it disappeared in the earth at the top. It 

 had been recently uncovered in the course of working, by the re- 

 moval of a thick superincumbent layer, which, I was informed, 

 had, in this as in other instances, the counter prints distinctly 

 marked in relief on its under surface, these upper projections 

 corresponding to the cavities below as exactly as a cast to its 

 mould. The whole length of the track, which was quite re- 

 gular, was from 14 to 16 feet, scarcely visible at first, as if the 

 sand had been too dry to receive the impression, but becom- 

 ing in a few steps perfectly well defined, and continuing so to 

 the very top. The surface on which the footsteps were im- 

 pressed was what the workmen technically call a clay-face, be- 

 ing, from a more copious admixture of clay than ordinary in 

 its outer coat, harder than the rest of the rock, and the seam 

 between it and the upper stratum having less adhesion, and con- 



* That is, when the fore-foot was advanced, and the hind-foot thrown back in 

 the act of moving forward. 



