williston: restoration of platygonus. 27 



Depth of mandible below the pre- 

 molars 36 37 45 35 40 49 44 47 



Depth obliquely at the symphysis . . 78 73 78 62 66 78 79 74 



Width at the canine alveoli 36 35 39 32 32 40 43 38 



Length of the lower molar series. . 78 82 80 .. 82 75 81 80 



*First premolar undeveloped. 



Length of the hiatus in advance... 52 54 54 .. 45 58 59 54 

 Transverse diameter of the condyle 24 23 25 . . 22 30 28 26 

 If they all pertain to one species, the figures will at least show the 

 extraordinary variations to which the species is liable. Perhaps the 

 most important differences are those of the lower jaws. The corres- 

 ponding measurements of the type of P. alcmanni Duges, given by 

 Leidy, are as follows: 



Height of mandible at condyle 100 



Height of mandible at coronoid process 104 



Depth of premolars 45 



Space occupied by the molar series 91 



Length of hiatus in advance of molars 62 



Breadth of condyle ^t^ 



Leidy says "The mandible with the lower teeth is an amplified 

 repetition of that of Platygonus compressus and appears to differ only 

 in the less backward position of the condyle, which in this direction 

 is less than the angle, as (it is) in the Peccaries." As will be seen 

 from the measurements, the jaw of P. alcmanni is actually smaller 

 than the largest of our specimens, while the position of the condyle 

 does not differ. The size of the teeth only is different. As from the 

 comparison of the types Leidy thought that the species was the same 

 as P. vctus, our specimens seem to unite all three. 



I confess my inability to decide whether or not these species are 

 independent. A careful comparison of all the known material 

 in the genus will I think be necessary for this purpose. Meanwhile, 

 I will use the name P. Icptorhinus for the present specimens. 



For further comparison, I give below comparative measurements 

 of other bones of the skeleton, those in the first column taken from 

 Leidy, the other two from our specimens. The bones whose meas- 

 urements are given in the third column belong to the male skull 

 figured; those in the seconil column are taken from the mounted 

 skeleton. The figures in the last column are of P alcmanni. 



1 2 3 -i 



Humerus, extreme length from greater tuberosity to 



outer condyle 190 200 222 



Length from head to posterior process of inner 



condyle 168 167 173 



Greatest breadth of proximal extremity 57 65 67 



Greatest breadth of head 33 39 39 . . 



Greatest breadth of distal extremity 39 42 44 . . 



