190 AN ATTEMPT TO DESCRIBE THE ANIMALS THAT MADE 



Distance between the tips of the hiteral toes, 1.1 to 1.7 inch; be- 

 tween the inner and middle toes, 1.1 to 1.4 inch; between the 

 outer and middle toes, 1 to 1,4 inch. Length of the middle toe be- 

 yond the others, 0.9 to 1.1 inch. Track shown, of th*e natural 

 size, on Plate 7, figs. 2 and 3 ; there being a slight difference be- 

 tween them. 



Locality. — Wethersfield, at the Cove ; on red shale. 



Species 3. Platypterna delicatula. (PI. VII. Fig. 4.) 



Ornithoidichnites delicatulus, Mass. Geol. Report, Plate 45, 

 fig. 40.' 



Nos. 103, 104, in Cabinet. 



Divarication of the lateral toes, 40° ; of the inner and middle 

 toes, 22° ; of the middle and outer toes, 18°. Length of the mid- 

 dle toe, 1.1 inch; of the inner toe, 0.65 inch; of the outer toe, 

 0.75 inch ; of the heel, 0.4 inch ; of the foot, 1.5 inch ; of the 

 step, 3 inches ; of the middle toe beyond the rest, 0.5 inch. Width 

 of the heel, 0.35 inch ; of the foot at the roots of the toes, 0.25 

 inch. Distance between the tips of the lateral toes, 0.6 inch ; be- 

 tween the inner and middle toes, 0.6 inch ; between the outer and 

 middle toes, 0.65 inch. Toes slightly curved. Track shown, of 

 the natural size, on Plate 7, fig. 4. 



Locality. — Wethersfield, at the Cove ; on red shale. 



Affinities of the Group. — The biped character of the animals 

 and their tridactyle feet would seem, were we to judge by living 

 animals, to ally them to birds ; while the deficiency of the hind toe 

 would lead us to regard most of them as Grallatores. The infer- 

 ence of Dr. Dana, also, from the coprolites of one species, is that 

 they were dropped by such omnivorous birds as those which pro- 

 duce the guano. I shall show in this paper, however, that biped 



