256 Robert Ilarkness, Esq., on Fossil Footprints. 



tives which induced the land-tortoises of the Bunter sand- 

 stone to leave their tracks in a west and east direction. Mr 

 Darwin, in his interesting narrative, gives an account of the 

 habits of the Testudo nigra, which seem to afford some in- 

 formation concerning the tracks which occur in the sandstone 

 of Dumfriesshire. " This tortoise is very fond of water, 

 drinking large quantities, and wallowing in the mud. The 

 larger islands," speaking of the Galapagos, " alone possess 

 springs, and these are always situated towards the central 

 parts, and at a considerable height. The tortoises, therefore, 

 which frequent the lower districts, when thirsty, are obliged 

 to travel from a long distance. Hence broad and well- 

 beaten paths branch off in every direction from the wells 

 down to the sea-coast; and the Spaniards, by following them 

 up, first discovered the watering-places. When I landed at 

 Chatham Island, I could not imagine what animal travelled 

 so methodically along well-chosen tracks. Near the springs, 

 it was a curious spectacle to behold many of these huge 

 creatures, one set eagerly travelling onwards with out- 

 stretched necks, and another set returning after having 

 drunk their fill." The circumstances attendant upon the 

 occurrence of footprints are such as to point out some con- 

 nection between the economy of existing land- tortoises and 

 those which, during the epoch of the Variegated sandstone, 

 were the inhabitants of the land ; and the regularity in the 

 direction of the tracks seems to indicate that these reptiles 

 sought the shore for the purpose of satisfying their thirst ; 

 and the clayey faces of some of the sandstone strata appear 

 to have had their origin in silty matter brought down by 

 some river, and deposited at regular intervals on the sandy 

 shore. To this river the different species of Chelichnus, 

 feeding upon the herbage of the land, repaired, leaving their 

 tracks on their return, after having satisfied their appetites. 

 With regard to the Rhynchosaurus, the relation of this form 

 to existing types is not sufficiently close to trace an analogy. 

 It is, however, probable, that this genus was strictly an occu- 

 pant of the shore ; and the form of its mandibles were such 

 as to lead to the conclusion, that these animals picked up 

 marine worms somewhat allied to the ArenicMa piscatoris, als 



