514 RICHARD SWAXX LULL ON 



of IV and V, 40". Length of digit 1, .().j(i iii.; of II, .080 m.; of III, .01)2 m.; of IV, .0!)8 

 m.; of V. .mill m. Length of foot. .lidC m. (pi. 72. fig. E). Length of step, about 

 .SOO 111. 



The type specimen is no. y\, of the Hitchcock cabinet, in high relief on coarse sand- 

 stone from South Hadley, Massachusetts. The countei-part, no. f, is taken some distance 

 below the surface on which the animal walked as the layer of red mud which intervened 

 was incapable of preservation. 



The studies of the bone restoration of the pes are largely conventional and the 

 results represent the most generalized diuosaurian foot which would Ije likely to be found 

 ill a bipedal dinosaur. The fifth digit is represented as vestigial. An accurate restora- 

 tion of the inanus skeleton will need the elucidation of further material. The genus 

 Otozoum shows some extremely interesting parallelisms with the Stegocephalian genus 

 Chirotheriuin which would lead one to suspect an actual relationship were it not for the 

 fact that the phalangeal formula of the earher form is such that that of Otozoum could 

 never have been derived from it. The parallelisms and contrasts are : — 



Chirotherium (pi. 72, fig. A-D). Otozoum (pi. 72, fig. E-G). 



Quadrupedal. Bipedal. 



Pes pentadactyl. Pes tetradactyl. 



Pads well developed. Pads well develojied. 



Plantigrade. Plantigrade. 



Claws rounded. Claws rounded. 



Web extending beyond the toes. Web extending beyond the toes. 



Phalangeal formula : 2. 3. 4. 4. 2. Phalangeal formula : 2. 3. 4. 3. 0. 



Manus pentadactyl. Manus pentadactyl. 



Claws reduced. Claws on II, III, and IV, developed. 



Web as in pes. Web reduced. 



Phalangeal formula : 2. 3. 3. 3. 3. Phalangeal formula: 2. 3. 3. 3. 3. 



Hand pointing forward. Hand turned inward. 



Habits apparently similai- as the j. reservation of the tracks is the same in each instance. Relative 



length of the foot to the stride is the same. 



Lower and upper Trias. Jura-Trias. 



(.'. burthii. C. sloretonensis. (9. moodii. 



Otozoum caudatum C. H. Hitchcock. 



Otozoiiin (■(iiidatvm C. H. Hitchcock, 71, p. xxi; '89b, pp. 110, 127. 



The present author seriously ([iiestions the validity of tliis .species, which is distin- 

 guished from 0. moodii only by the presence of a tail trace which could readily occur in 



