416 Concerning Foot-Prints. [ July, 
toe, connected with the metatarsal bone above the foot (as in 
many modern birds), which sometimes left a slight impression 
on the trodden surface. But the most striking analogy between 
the ancient tracks and the foot-prints of modern birds is to be 
seen in the fact that the phalanges, or joints of the toes, have 
the same numerical ratio in each; that is, in three-toed birds the 
inner toe has three, the middle one four, and the outermost one 
five phalanges. 
The force of these arguments in favor of the ornithie char- 
acter of the foot-prints has been somewhat impaired by the dis- 
covery of tracks bearing these peculiarities, but having, also, in 
connection with the large tridactylous impressions of the hind 
feet the much smaller five-toed tracks formed by the fore feet of 
the same animal, showing that they were made by a reptile. 
Sometimes a medial furrow accompanies such tracks, indicating 
that the animal possessed a long, strong tail. These discoveries, 
although proving that there have been three-toed reptiles, yet 
by no means prove that all the “bird tracks” were formed by 
such animals. 
We learn from the Triassic foot-prints that the strange creat- 
ures that impressed them not only inhabited the Eastern States 
in great numbers, but also that there was great variety in that 
ancient fauna. 
The accompanying figure of the 
foot-print known as Brontozoum 
giganteum, from Professor Hitch- 
cock’s report, represents the larg- 
est of the bird-like tracks found in 
the Connecticut valley. The foot- 
print represented in the figure as 
two and one half inches in length 
is in fact eighteen inches long and 
a foot in breadth, indicating, is 
only from the size of the foot-print, 
but from the manner in whic 
the trodden surface was crushed 
down, and also by the length of 
(Fre. 80.) BRONTOZOUM GIGANTEUM the stride that separates the steps, 
Peet: a bird of gigantic proportions, that 
must have far surpassed in size the largest of living birds, — al- 
though probably not exceeding the dimensions of the Dinorns 
giganteus, which at no very distant time inhabited New Zealand. 
