AVilliston.'I Birds. 53 



birds, or in the family of sea-gulls and terns. That the track 

 is probably that of the right foot, rather than the left, is indi- 

 cated by the wider separation of the outer toe from the middle 

 toe, resulting from the greater versatility of the outer toe as 

 compared with the inner toe, a character illustrated in many 

 families of existing birds, and carried to an extreme in the 

 cuckoos and the woodpeckers, in which the outer anterior toe 

 is entirely reversed in its direction and becomes a backward- 

 pointing member." ( See opposite page.) 



"It will be seen, from the accompanying cut, that our bird 

 track exhibits the imprint of all four of the toes. The outer 

 anterior toe is represented for fully two-thirds of its length. The 

 middle and inner anterior toes are entirely impressed, even to 

 the claws at their extremities — the claw being very distinctly 

 marked upon the middle toe. The ball of the foot has left a 

 very deep impression, and the posterior toe has made an unmis- 

 takable imprint upon the sand similar to those made at the 

 present time by birds whose hind toes just reach the ground. 

 That this impression is avian in character, rather than reptilian, 

 is evident from the imprint of the hind toe, for no dinosaur or 

 other reptile, either recent or extinct, is known to have a back- 

 wardly directed toe. . . . The small size of our Dakota 

 track is a confirmatory indication of its avian character. It 

 measures only two inches from anterior middle claw to claw of 

 posterior toe, being a little larger than the foot of Prof. O. C. 

 Marsh's Icldhyornis victor as restored by him in his famous 

 monograph of the Odontornithes." 



The slab on which were the prints described by Mudge was 

 left at the Agricultural College. In the general neglect of 

 Mudge's collection, after his connection with the institution 

 ceased, the specimen has been lost. The specimen described by 

 Snow is now preserved in the University of Kansas museum. 

 The description and figure given by Snow describe the specimen 

 sufficiently well. I agree with him in his conclusions. The 

 print is in all probability that of a bird. 



