IMPRESSIONS OF THE PAST 43 



hand that Dr. Kaup christened the beast sup- 

 posed to have made them Cheirotherhim, beast 

 with a hand, suggesting that they had been 

 made by some gigantic opossum. As the 

 tracks measure five by eight inches, it would 

 have been rather a large specimen, but the 

 mammals had not then arisen, and it is gener- 

 ally believed that the impressions were made 

 by huge (for their kind) salamander-like creat- 

 ures, known as labyrinthodonts, whose re- 

 mains are found in the same strata. 



Footprints may aid greatly in determining 

 the attitude assumed by extinct animals, and 

 in this way they have been of great service in 

 furnishing proof that many of the Dinosaurs 

 walked erect. The impressions on the sands 

 of the old Connecticut estuary may be said to 

 show this very plainly, but in England and 

 Belgium is evidence still more conclusive, in 

 the shape of tracks ascribed to the Iguanodon. 

 These were made on soft soil into which the 

 feet sank much more deeply than in the Con- 

 necticut sands, and the casts made in the nat- 

 ural moulds show the impression of toes very 

 clearly. If the animals had walked flat-footed, 



