NO. 3 



GRAND CANYON FOSSIL FOOTPRINTS — GILMORE 



49 



Examination of the ty])e (see pi. 15) shows that the animal was 

 in the habit of placing the hindfoot directly in line with but a variable 

 distance behind the forefoot, never overlapping. That the digits were 

 flexible is indicated by the strongly bent ends of digits three and four 

 in the lower impression of the pes as shown in figure 21, whereas the 

 very next impression forward shows them j^erfectly straight. Since 

 the straight form of digits predominates they are regarded as repre- 

 senting the normal shape of these toes. 



Comparative Measurements 



* Measurements of Hytopus hardingi taken from Matthew's illustration. 



Matthew ' depicts a fore- and hindfoot of Hylopus liarduigi which 

 in the explanation of figures he attributes to the right side. By com- 

 parison with the tracks of IJylopiis hcnnitanns now before me, and 

 especially with Matthew's figure 2. plate 6. it becomes at once appar- 

 ent that they pertain to the left side. It will be noted that in Mat- 

 thew's illustration of the hand, the side from which the first digit 

 would spring is left unfinished (see fig. 23), implying that the evi- 

 dence for its absence was inconclusive. In view of the close resem- 

 blance to the specimen here described and in their close agreement 



Proc. Trans. Roy. Soc. Canada, Vol. 10, 1904, figs, la and ib. 



