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PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [June 21, 







OQ 



and pachydactylous ; the inner toe alwa3'S 

 the shortest ; the middle one always the 

 longest, and all of them directed forward ; 

 there are no satisfactory distinct pha- 

 langeal impressions, but in many examples 

 the distal extremity of the terminal joint 

 is distinctly traceable. 



The impressions are disposed in tracks, 

 and the toes of every two successive marks 

 turn alternately right and left. 



The impressions differ in size and pre- 

 sent a variety in form ; the stride also va- 

 ries in length. The impressions or marks, 

 however, composing a single track or 

 line are uniform in size, and also uniform, 

 or nearly so, in distance from each other ; 

 they point also in one general direction. 



The marks do not occur in a right line, 

 as in the case of the tracks of gallinaceous 

 birds and in certain fossil footprints from 

 the Connecticut Valley, but the two rows 

 ot tracks made by the right and left foot 

 are immediately to the right and left of 

 the line of direction, and the axis of the 

 foot is turned inwards a few degrees to- 

 wards that line. In this respect, but in 

 this only, these impressions present a 

 striking resemblance to the fossil foot- 

 prints of the Herpedactylvs rectus, and 

 coincide vrith the habit of some recent 

 birds. 



The best of the natural casts of these 

 impressions in my collection have a hemi- 

 spherical or heel-like prominence, which 

 is lateral and always on the side of the 

 outer or longer lateral toe*. In iinpres- 

 sions this peculiarity is not so ob-\"ious, as 

 this part of the surface in usually concealed 

 by adherent portions of the rock ; but even 

 in these instances, sufficient eA^idence exists 

 to prove that the character is uniform. 



It is important to add that, while my 

 former evidence was derived from casts 

 standing in relief on the under-plane of 

 the overlying deposit, the present is fur- 

 nished bymarks on the upperandrippledf 



* Probably tbe expansion of the proximal 

 phalanx. See also Quart. Geol. Journ. vol. viii. 

 pp. 396, 397, figs. 1 cSc 2. 



t \Miere the surface had evidently been only 

 recently excavated, I observed well-defined ripple- 

 marks associated with the footprints. 



n Avai 



