72 The American Geologist. August, i89b 
The horn-core of B. ferox, according to Prof. Marsh, in- 
dicates an animal much larger than the existing bison, having 
very powerful horns. He gives the following measurements: 
Length, when complete, over 500 millimetres, radius of the 
inner curve about 400 millimetres. The largest end has a 
diameter of 125 millimetres and the smaller at a distance of 
300 millimetres measures yy millimetres.* 
Bison alleni has its greatest and least diameters near the 
base, 140 millimetres, and no millimetres, and at a distance of 
300 millimetres toward the smaller end the diameters are 100 
millimetres and 90 millimetres. Prof. Marsh also observes: 
"The discovery of these two lower Pliocene species of Bison 
suggests the probability that this form is a new world type, 
although it has generally been credited to the other hemis- 
phere." 
Comparing these two fossil cores with the cores of B. ari- 
zonica I find that the difference between them and the cores of 
B.arizonica are greater than between each other. Both B. ferox 
and B. alleni are longer in proportion to their thickness than 
in B. arizonica, and the curvature is greater. 
For purposes of comparison of some of the chief dimen- 
sions of the B. primigenius of Europe and of the more closely 
related forms of America, I have prepared the tabulated state- 
ment. 
THE SIGNIFICANCE OF THE FRAGMENTAL ERUP- 
TIVE DEBRIS AT TAYLOR'S FALLS, MINN.t 
By N. H. WiNCHELL, Minneapolis, Minu. 
The conglomerate at the celebrated geological locality of 
Taylor's Falls has been known since its first description by 
Owen. It has been described later by Kloos, Strong, Irving 
and by the writer, and recently been carefully examined by 
Mr. Berkey in the course of his mapping of the region for his 
thesis lately published in the American Geologist. 
Dr. Owen considered the eruptive rock of later date than 
In the foregoing table I have given these measurements in their 
equivalents in English inches in order to facilitate direct comparisons. 
fRead before the Minnesota Academy of Natural Sciences, Dec. 30th, 
1897. 
