Marsh Collection, Peabody Museum. 121 



(primarily plantigrade), Procyon (subdigitigrade), and Felis 

 (digitigrade), we see that the planes of the distal facets give 

 certain indication of the modes of progression." 



In other words, by an examination of the distal ends* of the 

 metapodials, one can certainly tell whether these bones are 

 carried in a plane parallel to the surface upon which the animal 

 walks (plantigrade), or perpendicular to it (digitigrade), in the 

 act of progression — a very important and valuable discovery if 

 true. ISTow if there is any truth in this hypothesis, it appears 

 to me that the character of the distal ends of the metapodials 

 in two such typical and widely different-gaited animals as a cat 

 and a bear would exhibit such marked and unmistakable differ- 

 ences in these particulars, that one would be able to tell at a 

 glance whether the animal in question were plantigrade or 

 digitigrade. As a matter of fact, however, and, I may add, of 

 the most common observation and knowledge, the amount of 

 difference in the distal articular surfaces of these bones in the 

 cat and bear is so surprisingly small, that, in themselves, they 

 do not give the faintest or slightest hint at such marked differ- 

 ences in gait. According to Professor Osborn's own showing 

 in his diagram, the differences in the extent, arrangement, and 

 planes of these facets, in the two animals, are very slight 

 indeed. It should be here observed that in the diagram, if the 

 metapodial of the bear is placed in its natural position with 

 reference to the phalanges, the corresponding bone of the cat 

 must be rotated to the left somewhere in the vicinity of ninety 

 degrees, in order to represent the position which it naturally 

 assumes in the foot of that animal. If, therefore, the planes 

 of these facets fail to record a difference of nearly ninety 

 degrees of arc, in determining the position of the bone in this 

 case, it is pertinent to inquire how far they can be . trusted in 

 any other case. It is sufficiently obvious, I take it, that if the 

 position of the metapodial is incapable of being fixed by this 

 method, it is practically worthless in the further determination 

 of the gait of the animal, since the position of these bones is 

 the all-important factor in the case. 



Let us next turn our attention to the phalanges. I quote 

 again from the paper in question, p. 271. u As regards angula- 

 tion, Patriofelis is shown to occupy a position intermediate 

 between Procyon and Felis, with a decidedly angulate foot, 

 the angles between phalanges 1 and 2 being especially acute. 

 This proves that the metapodials, as well as phalanges 1 and 2, 

 were raised off the ground by plantar and palmar pads as in 

 Felis. Taking a conservative view, the feet of Patriofelis 

 may be described as subdigitigrade in position. The straight 

 terminal claws indicate that they entirely lacked the grasping 

 and tearing power developed in Felis P 



Using the previous examples, the cat and the bear, in the 



