FOSSIL FOOTPRINTS OF THE JURA-TRIAS. 515 



O ,aoodii provided the specimens showed the animal's track under favorable circum- 

 stances, that is. iust before stopping. The other character, that of a forwardly directed 

 " thumb " (hallux) as against a recurved one in O. moodii is hardly a vahd distinction for 

 the reason that the curvature is not a constant character, in fact it is of rare occurrence. 

 The type specimen of tliis species, if such it is, is in the museum of Wesleyan 

 university, at Middletown, Connecticut. 



? Otozoum parvum C. H. Hitchcock. 

 Otozown parvnm C. H. Hitchcock, '89b, pp. 119, 122, 127. 



Specific characters. Pes : divarication of digits I and II, 24° ; of II and III, W ; of 

 III and IV, 14°; of T and IV, 54°. Length of digit I, .U76 m.; of II, .120 m.; of III, .128 

 m- of IV 102 m. Length of foot, .190 m. On one slab from Milford, New Jersey, 

 preserved hi the Geological museum, at Lafayette college, a fifth digit, arising near the 

 base of the fourth, is seen, very similar indeed to Chirotherium. 



Manus : divarication of digits I and II. 29= = of II and III. 16° ; of III and IV, 4^) _; 

 of IV and V, 14°. Length of digit I, .030 m.; of II, .034 m.; of III, .035 m.; of IV, .02o 

 m • of V 020 m. Length of entire impression, .075 m. 



" This form is not Otozoum ; in fact it suggests Chirotherium much more strongly, and 

 further study may prove the identity of this species with the latter. 



The type specimen is preserved in the museum of Lafayette college, Easton, 



Pennsylvania. 



Order INCERTAE SEBIS. 



Forms hahituaUy bipedal . 

 Genus Platypterna E. Hitchcock. (Broad heel.) 



Platypterna E. Hitchcock, '45b, p. 25; '58, P- 83. 



Generic characters. Bipedal, tridactyl, plantigrade or digitigrade, generally with a 

 broad, rounded heel. Digits narrow, without pad impressions and but rarely showmg 



distinct claws. . . t«: u +,> 



This is one of the " leptodactylous " genera whose characters it is very chfficult to 

 make out. It would seem best to place it provisionally with the carmvorous dinosaurs 

 because of the bipedal gait aud dinosauroid character of the toot. 



