AMERICAN GEOLOGISTS AND NATURALISTS. 19 



in a straight line, the toes or marks in all such cases being alternate ; 

 that is, if the right foot be presented on the rock, the left would next 

 follow, and thus right and left in regular succession, sometimes with 

 many repetitions. In other instances, the foot-marks presented no 

 determinate direction or order, as might naturally be supposed of a 

 bird or any other animal having no particular place or object in 

 view. 



In all cases where a succession of tracks was observ^ed, there was 

 a uniform correspondence as to size, and considerable regularity as 

 to distance between the tracks. Whatever deviations w^ere observ- 

 ed, they were not greater than might be supposed to take place in 

 animals possessed of voluntary motion. 



On some surfaces, not vmfrequently one or more different kinds of 

 track were exposed, belonging, as was reasonably conjectured, to 

 different species and genera of ornithichnites. 



That the slaty material of the rock showed that the impressing 

 body possessed force or weight, for frequently the thin layers or 

 lamina3 were bent downwards for an inch or more, and that the mud 

 of which the slate was formed was of a highly adhesive or tenacious 

 character. 



In all cases the foot-marks, or part impressed, was the fixed part 

 of the rock ; the part removed when the lower side was turned 

 upwards, showed the cast or what corresponded with the toes or 

 foot. That no trace of any organic matter could be perceived occu- 

 pying the cavity or mould, the cast or part in rehef being in all res- 

 pects like the material of the rock of which it formed a part. 



Finally, that the foot-marks, belonging to a group of rocks which 

 must be considered to have been produced by the same general 

 causes which gave rise to the new red sandstone of Europe, are 

 referable only to that sandstone. This sandstone presents foot- 

 marks in many localities, though comparatively but a few years 

 have elapsed since attention has been called to them. Some of the 

 specimens have reached this country, and had they not, the infor- 

 mation is well given by Dr. Buckland in his Bridgewater Treatise. 

 The most remarkable of these foot-marks, are those of the Cheirothe- 

 rium from the quarries of Hesburg, near Hildburghausen in Saxony, 

 greatly resembling a fleshy human hand. These, in the drawing and 

 in the specimen which we have seen, are alternately right and left. 

 Other foot-marks have been observed by Mr. Linse in the same sand- 

 stone, he having made out four species of animals, some of which 

 are conjectured to belong to gigantic Batrachians. Near Dumfries, 

 the foot-marks of animals, probably tortoises, were obtained from 

 the same sandstone, but as yet no tracks like those of New Eng- 

 land have been discovered. 



The facts, &c. which led to a different conclusion are these. 

 First, that the forms, assumed by fucoidal plants were numerous 

 and imitative, some resembling the tail of a rooster, the cauda galli ; 

 another, which was like unto a large claw or paw, and which may 



