20 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. // 



prints, even when the tracks seem to be fairly well impressed. Of 

 more than 30 distinct tracks, none registers more than three toes, 

 and were it not for the deformity of the toes of the right hindfoot, 

 showing that the tracks of both type and paratype were made by the 

 same animal, there might be some doubt as to their reference to 

 the same species. 



The digital formulae oi B. sydnensis and B. abcissa (figs. 12 and 

 13) as determined by Matthew, are 4-3 and 4-4 respectively. That 



Fig. 12. — Baropesia sydnensis (Dawson). A, Mould of right 

 forefoot; B, mould of right hindfoot. * natural size. (After 

 Matthew.) 



both may have additional toes which did not register seems quite 

 probable, especially in the light of the two series of tracks discussed 

 above. That Matthew was cognizant of such a possibility is indi- 

 cated by his comment on the pes of B. sydnensis that " the first digit 

 may be potentially present." Considered from the evidence fur- 

 nished by this new material, it would seem quite certain that B: 

 sydnensis has a formula of 5 and 4 digits instead of 4 and 3. There 

 is also reason for thinking that Matthew may have been mistaken 

 in his identification of the relative positions of the two tracks. In 

 the narrowness, fore and aft, of the sole impression, the divergence 

 of digit one, and in the relative size and arrangement of the other 



