164 Fossil Footprints of the Connecticut Valley. 



tiles are inaccessible. But it is hoped that these discoveries will 

 attract the attention of naturalists who have given to the study 

 of this class of animals particular attention. In illustrating the 

 meaning of these new fossils, the difficulties to he encountered 

 are superior to those connected with ornithic imprints. With 

 the great class of birds we become insensibly familiar by con- 

 stant association ; but the natural element of the Batrachians, 

 their obscure retreats, and the meagre opportunities of seeing the 

 imprints of their feet, are obstacles which combine to baffle ac- 

 curate comparisons. The progression of all birds when moving 

 upon the feet is by the same method nearly, but in the cold 

 blooded amphibious Batrachians there is in this respect conside- 

 rable diversity. In frogs, toads, &c. it is by a rapid succession of 

 leaps ; while in salamanders, lizards, and the like, the method is by 

 walking. This is the case with the German footsteps and those 

 now under consideration. Yet, as has been intimated, when we 

 become as familiar with recent footprints of Batrachians as we 

 now are with those of existing birds, the true relations of the 

 extinct varieties can be determined. The affinity of the Ameri- 

 can and German examples is sufficiently intimate to remove all 

 doubts of their mutual relations ; but in the absence of bones, 

 of which no instance has yet occurred in the stratified sand- 

 stones of the Connecticut River, we must not omit when oppor- 

 tunities occur, to institute comparisons with the footprints of 

 those living animals that appear to be most nearly allied to them. 

 It may be safely asserted upon this principle, that the quadrupedal 

 impressions from Turner's Falls are those either of Batrachian 

 reptiles or of marsupial mammalians, of which two distinct spe- 

 cies at least exist, and most probably three, as will be directly 

 seen. 



It is the design of this article to communicate facts rather than 

 to draw the necessary inferences ; and with this view I have 

 been at considerable pains To prepare an accurate plate, which 

 the Editors have deemed sufficiently important to justify the ex- 

 pense of publication, and to this drawing I would respectfully 

 invite the particular attention of those naturalists whose oppor- 

 tunities or pursuits may lead them to explore the laminated beds 

 of new red sandstone. Upon the Connecticut River localities 

 especially, and doubtless in most others, the minute traces of 

 animals can be detected only by vigilant attention ; and the 



