248 AN ATTEMPT TO DESCRIBE THE ANIMALS THAT MADE 



Remarks. — It may seem an insuperable objection to considering 

 the sketches of PI. 23, fig. 5, as the feet of the same animal, 

 that they point in opposite directions. But a reference to the 

 feet of some reptiles will show that such would be the tracks 

 which they would make. Plate 23, fig. 6, is an outline of the 

 Algyra barbarica, copied from Griffith's Cuvier, Vol. IX. p. 212. 

 Of a similar character is the outline on Plate 23, fig. 7, of the 

 Salamandra Beecheyi, copied from the Zoology of Beechey's Voyage, 

 Plate 31, fig. 3. 



I would not intimate that the Harpagopus giganteus was a batra- 

 chian or lacertilian ; for I have no evidence of another set of tracks 

 corresponding to those sketched on Plate 23, fig. 4. Indeed, I 

 know of no living animal whose feet correspond to these impres- 

 sions. Yet some crustaceans have bifurcated extremities ; as was 

 the case with some encrinites. Then one cannot but think, in this 

 connection, of the ichthyopodulhes of Dr. Buckland, or petrified 

 track-ways of certain ambulatory fishes, whose fins struck the muddy 

 bottom. 



Locality. — Turner's Falls, where it was obtained by Mr. Marsh; 

 and he has specimens in his cabinet. 



Species 2. Harpagopus Hudsonius. (PI. XVIII. Fig. 2.) 



No. 127 in Cabinet. 



Rows of tracks two, parallel, about a foot apart ; feet didact}- 

 lous ; toes diverging about 40° ; unequal in length ; blunt ; length 

 from 2 to 3.5 inches ; the axis of the foot lying nearly at right 

 aneles to the direction in which the animal moved. One foot of 

 two toes shown, of the natural size, on Plate 18, fig. 2. Plate 24, 

 fig. 1, shows a greatly reduced oudine of a slab in my cabinet, 

 taken from a sidewalk in New York. 



