1856.] BINNEY FOOT-TRACKS AT TINTWISTLE. 353 



an animal, but whether a biped or a quadruped no one ventured to 

 decide. This opinion was maintained, notwithstanding the varying 

 characters of the markings. One gentleman suggested that a tree 

 with a projecting stump, carried by short waves towards a sandy 

 beach, might cause such appearances by allowing the stump to touch 

 the wet sand each time it came into the trough of the wave. This 

 hypothesis would no doubt account for the regular distances of the 

 impressions, and the sand having all been pushed out on one side ; 

 but it would not account for the two distinct projections of sand ; 

 besides, there is this objection, — waves so short as the distances be- 

 tween the impressions are not now very commonly met with. 



By the liberality of Mr. Rhodes, the impressions Nos. 1, 2, and 3 

 are now in the museum of the Manchester Geological Society. On 

 seeing these last year. Sir Charles Lyell expressed himself much in- 

 terested in them, and it was at his instance and request that this 

 sketch was written, the writer having some years since given an ac- 

 count of the specimens for a local print. Lately, Mr. Waterhouse 

 Hawkins has examined the specimens, and he is strongly inclined to 

 believe that the impressions are the track of an immense Chelonian 

 Reptile, resembling the Chelichnus gigas, figured by Sir William 

 Jardine in Plate I. of his ' Ichnology of Annandale,' or the C. Titan 

 which the same author alludes to, but does not figure. This opinion 

 is further borne out by the varying character of the impressions, and 

 it accounts for the pushing out of the wet sand at two successive 

 times, namely first on the planting of the fore-foot of the animal, and 

 then of the hind foot in the same or nearly the same place, and for 

 the similar quantity of wet sand displaced and thrown back in each in- 

 stance. In tracks of Batrachian Reptiles, like those of the Labyrintho- 

 don of the Trias, the impressions are nearly in a straight line, and the 

 mark of the small fore-foot is not always seen, even when the impres- 

 sions have been taken in a fine stiff red clay, resting on a fine sand, 

 and partly hardened by the sun. In the impressions described in this 

 paper there is a probability that they were made on soft sand under 

 water, for the sides of the matrix have given way and partially run 

 into the moulds in a manner such as we scarcely ever see now in foot- 

 prints made by animals on a sandy beach. Under these conditions, 

 we could hardly expect to find a distinct fore-foot mark, even if the 

 track were that of a Lahyrinthodon, which it resembles in its straight 

 direction more than that of a Chelichnus. But no animal of the genus 

 Lahyrinthodon appears to have pushed out the wet sand behind, in 

 the same way that the Tintwistle fossils show. The Chelichnus 

 shows this protrusion ; therefore it is more probable that the impres- 

 sions under consideration were made by an animal of the last-named 

 genus, or one allied to it. The distance (in breadth) between the 

 hind and fore foot-marks, which is certainly greater than that seen 

 in the tracks of the Lahyrinthodon, may have disappeared by the 

 two impressions being nearly opposite to each other, having run 

 together and formed one wide hole, as in specimens Nos. 1, 4, and 

 5 ; whilst in specimens Nos. 2 and 3, the hind foot came nearly in 

 the same place as, or only just behind, the impression of the fore foot. 



