182 On the Foot-marks ofAnivials in Rocks. 



imprints to the saurians of the ancient world ; but the plump 

 form of the sole of its feet, and the character of the gait of cro- 

 codiles, which I have observed so often on the shores of the 

 Orinoco, are wholly opposed to this hypothesis; and at the 

 epoch of the monocotyledons of the coal formation, vast islands 

 of it were dry, and might easily have afforded nourishment to 

 the mammalia. 



Professor Link has lately published a notice regarding the 

 Hildburghausen foot-marks, but he suspects them to be impres- 

 sions of amphibious animals, not of quadrupeds, as mentioned 

 by Humboldt. 



The plain of Hildburghausen, says Link, situated at the foot 

 of the mountains of Thuringia, is formed of variegated sand- 

 stone, sometimes rising into little hills. This sandstone is em- 

 ployed for building, and it was in a quarry dug to obtain it, that a 

 master mason named Wenzer, first noticed, about a year since, 

 some impressions which appeared to be of an unusual descrip- 

 tion. He mentioned the circumstance to M. Sickler, who pub- 

 lished a description of them, with figures, in a letter to M . Blu- 

 menbach. This letter appeared in the month of January in the 

 same year, consequently a very short time after the discovery. 

 Since that period, marks have been found in four quarries, near- 

 ly a league distant from each other, the last of them near the 

 town of Hildburghausen. M. Weiss of Berlin and myself vi- 

 sited three of these quarries in the month of August of the pre- 

 sent year, and have seen all the stones with foot-marks, which 

 have been collected in the house of M. Wenzer and at Hild- 

 burghausen. The following is the appearance of these marks. 



Immediately beneath the surface of the soil, there are alter- 

 nating beds of sandstone and clay, usually about ten feet in 

 thickness. After the removal of these beds, which do not afford 

 stone fit for building, we come to a bed of more indurated sand- 

 stone, not exceeding half a foot in thickness, resting on a bed of 

 clay, the thickness of which is very variable. At first nothing 

 extraordinary is seen on this bed, unless that it presents very 

 few fissures, and seems to be of a single piece. It is necessary 

 to remove pieces of it, and turn them over, in order to discover 

 the marks. They are always on the under side of the bed, and 



