38 ANIMALS OF THE PAST 
versally believed to be those of birds. So itis 
greatly to the credit of Dr. Deane, who also 
studied these footprints, that he was led to 
suspect that they might have been made by 
other animals. This suspicion was partly 
caused by the occasional association of four 
and five-toed prints with the three-toed im- 
pressions, and partly by the rare occurrence of 
imprints showing the texture of the sole of the 
foot, which was quite different from that of 
any known bird. 
In the light of our present knowledge we 
are able to read many things in these tracks 
that were formerly more or less obscure, and 
to see in them a complete verification of Dr. 
Deane’s suspicion that they were not made by 
birds. We see clearly that the long tracks — 
