54 E. Hiichcock on Fossil Footmarks of the Connecticut Valley. 
sometimes on the other; now and then on both sides, and then 
crossing the line of tracks, so as to seem to have no connection 
with them. In general, however, it seems as if some flipper-like 
animal, whose feet are all less than an inch. I have hence been 
sometimes inclined to believe that the trails were made by some 
animals swimming along near the bottom, and occasionally 
striking and grooving it with its flippers or fins. But my more 
mature conviction is, that they are gonnected with the tracks. 
But it needs a series of expensive drawings to make the facts 
fully understood without specimens 
. But to return to the Anomeepus ; which characters shall we 
are the most numerous a striking. It may, after all, have been 
a bird, of so low a e, however, that, even with its skeleton 
before him, the sa would hesitate where to place it, as in 
the case of the Arc teryx. 
7. This conclusion, to which the facts and reasoning have 
conducted me, not without remaining doubts, would, ae long 
since, have appeared very absurd. But, if it could be itted, 
see what a relief it would ap to difficulties: If the ‘Auctnsepil 
were a lizard, or marsupial, w must give up that firmly estab- 
lished law of correlation hints aaale us to distinguish different. 
classes of animals by the number and order of phalanges; but 
if it were a bird, that law can still be reckoned upon among the 
fossil as well as living animals, If a bird, we can see also how 
it was that it generally walked upon two feet, although it had 
another tee to be used perhaps for several purposes, but rarely 
for locomoti 
8. If we a presume that the Anomcepus was a bird, it lends 
strong confirmation to another still more important conclusion, 
which is, that all the fourteen species of thick-toed bipeds, which 
I have described in the Jehnology, and in this paper, were birds. 
In case, if we can retain the law as to the phalanges, all the 
2 6 4 of the animal, as made known by their tracks, belong — 
to with little variation from the existing bird type. They 
is unquesti eS ‘Since they are the most abundant 
cks Ih vi nds of them, and had fore © 
| am seare they 0 would occasionally have left some 
