AMPHIBIAN FOOTPRINTS FROM THE MISSISSIPPIAN 



OF VIRGINIA 



E. B. BRANSON 

 Oberlin College 



In the summer of 1908 a geological field party from Oberlin Col- 

 lege collected a series of amphibian footprints from the Mississippian 

 of Giles County, Virginia. The horizon of the prints was near the 

 bottom of the Hinton formation, but as the line of demarkation 

 between the Hinton and the underlying Bluefield formation is not 

 sharply drawn it was impossible to determine the exact distance above 

 that contact. *The Bluefield in this region is~ about 1,300 feet thick 

 according to Campbell, and the Hinton about the same thickness. 

 The horizon of the tracks is about 1,300 feet above the Greenbrier 

 limestone which lies just below the Bluefield, and 1,300 or 1,400 feet 

 below the equivalent of the Pottsville. According to Stevenson the 

 Bluefield and Hinton are to be correlated with the upper part of the 

 Mauch Chunk of Pennsylvania, and it was from the Mauch Chunk 

 of Pennsylvania 700 feet below the Pottsville conglomerate that 

 Smiropus prlmevus Ixa was collected. 



The Hinton shales, like the Mauch Chunk, seem to have been sub- 

 aerial in origin and are made up for the most part of variegated shales 

 interbedded with thin layers of argillaceous, fine-grained sandstone. 

 The footprints occur in fine-grained sandstone, and remains of land 

 plants are not uncommon in the same beds. No marine fossils were 

 noted by the writer in his examination of the Hinton excepting in 

 one horizon, and that probably represented a brief transgression of 

 the sea over delta flats. The fossils were rare and belong to only 

 four or five species. 



Twenty-two footprints made by one animal walking in a straight 

 course were collected in a slab. They give the impression of having 

 been made by a bipedal animal for part of the distance, but after the 

 fourth print of the right foot impressions of the forefeet appear. 

 The distance from tip of toe to tip of toe in the first prints is about 



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