222 AN ATTEMPT TO DESCRIBE THE ANIMALS THAT MADE 



may be seen in the possession of Mr. Leonard, Mr. Marsh, or my- 

 self, by naturalists who would make sure of the correctness of my 

 delineations. I will add, however, that the examination of the char- 

 acters of this genus has cost me more labor and perplexity than that 

 of any other described in this paper ; and it would not be strange, 

 if different observers should not entirely agree as to some of the 

 features of its tracks. 



Species 1. Anomcepus scambus. (PI. XIII. Figs. 1 -6.) 



Am. Jour, of Science, Vol. XLIX. p. 80, and Vol. III. p. 78, 

 New Series. 



Hind foot Pachydactylous; three-toed (four-toed?). Divari- 

 cation of the lateral toes, 45° to 50^ ; of the inner and middle toes, 

 20° to 25°; of the middle and outer toes, 20°. Toes usually 

 nearly straight, but sometimes curved. Heel 4.2 inches long, ex- 

 panding towards the posterior part. Lower leg above the tarsal 

 joint sometimes making an impression on mud (see PI. 13, fig. 4). 

 Phalangeal impressions on mud three (?) by the inner toe, 0.7, 0.7, 

 0.8 inch, respectively; three by the middle toe, LI, 1, 0.7 inch; 

 and five by the outer toe, 0.8, 0.8, 0.6, 0.6, 0.6 inch. Lateral dis- 

 tance between the extremity of the heels in the two tracks, 4 to 

 5.8 inches. Angle between the axis of the foot and the line of 

 direction, 0° to 20°. Distance between the tips of the lateral toes, 

 2.7 inches; between the inner and second toes, 1.9 inch ; between 

 the second and third, L8 inch. Projection of the middle toe be- 

 yond the rest, 1 .2 inch. Length of the middle toe, 3.2 inches ; of 

 the inner toe, 2.4 inches ; of the outer toe, 3.3 inches ; of the foot, 

 6 to 8 inches ; of the step, usually about 9 inches. 



Fore feet. — Quinquefid, pachydactylous ; digitigrade. Divari- 

 cation of the outer toes, excluding the hind toe, 75° to 90° ; of 



