DESCRIPTION OF THE PLATES. 



Plates No's 1 and 2 are footprints of existing living animals, for comparison. 



PLATE I. 



Fig. 1, Tracks of a Frog. 



Figs. 2 and 3, Tracks of recent small Birds. 



PLATE II. 



Fig. 1, Track of a Hen. 



Figs. 2 and 3, Tracks of Chickens. 



PLATE III. 



Fig. 1 was described by Dr. Deane in a Communication to the American Academy 

 of Arts and Sciences in 1849, as follows : 



This is the smallest example of ornithic footprints known. It is a left foot, 

 and displays the marks of peculiar organization tolerably well. The toes are 

 massive ; the inner one showing two lobes distinctly, and the middle and outer 

 ones their respective number, but indistinctly ; the nails are also slightly impressed. 

 The impression of the tarsus, or distal extremity of the tarso-metatarsal bone, is 

 perceptible, and, altogether, it is the best example of this most diminutive species 

 I have seen. The step is four inches. This species is rare, and has been found 

 only at Turner's Falls. 



Fig. 2 was also described by Dr. Deane in his communication above referred to, 

 as follows: 



