676 U. S. P. R. R. EXP. AND SURVEYS ZOOLOGY GENERAL REPORT. 



The hair of this species is very coarse and spongy in the summer, coarser than in the deer, 

 rather finer than that of the antelope, which it resembles in crimping, sponginess, brittleness, 

 and coarse thread-like appearance. In summer there appears to he no under coat, but in 

 winter there is probably more or less of it, as in an autumn specimen there is a considerable 

 amount of a rather fine wool, of short staple, but probably never in sufficient amount to be of 

 any value. 



According to Mr. Audubon, a large bighorn will weigh about 350 pounds, perhaps more. 

 It is larger than a Virginia deer, much more so than the domestic sheep. 



The horns are of immense size, and provided with transverse ridges or constrictions. They 

 arise above the eyes, the middle of their root being about opposite the posterior border of the 

 orbit. The inner bases of the horns are almost in contact, separated only by the space of half 

 an inch. They rise for a short distance, then curve gently backwards, diverging throughout 

 their course until they have described rather more than a semi-circle. Their section is rather 

 triangular throughout, becoming much compressed towards the apex, which is twisted outward. 

 Their curve is such that, with the base of the skull in a horizontal plane, the truncated tip 

 comes back to about the vertical plane of the occiput, its upper edge about one and a half inches 

 below the horizontal plane. In one old animal the horns are 19 inches apart at the tip ; they 

 measure 15^ inches in circumference at the base, and 28 inches in length around the curve. 

 They weigh 18 pounds with the perfectly clean skull, lacking the end of the nose and the 

 lower jaw. In the specimen brought by Captain Stansbury from the Rocky Mountains, how 

 ever, the horns are 18 inches in circumference at the base ; the horn along the convexity 

 measures 36^ inches, and the tips are 18 inches apart. 



The section of these horns at the base is sub-triangular, the outer and upper sides of the 

 triangle nearly straight, the inner convex. Thus there are two planes to the outline of the 

 horn, and one curved surface. The exterior face of the horn is quite plane, the application of a 

 straight edge showing it to be only slightly convex. In no one of many horns have I seen 

 anything like the very decided valley (or notch in cross section) exhibited in Middendorff 's 

 figure of his supposed 0. montana, from the Sea of Okotsk. The- upper [face of the horn is 

 likewise only gently convex, the two planes meeting at less than a right angle. The remaining 

 face of the horn, or that constituting the internal and posterior surface, is convex. Generally 

 the transverse diameter of the horn at its base is as long, a little longer, or but little shorter 

 than the antero-posterior. 



In a bighorn from California, on the 35th parallel, fig. 30, the horns are less massive, measur 

 ing only thirteen inches in circumference at the base, and two feet along the external upper ridge, 

 along the convexity of the curve. The plane character of the exterior and superior faces, is 

 very decided ; as is also their triangular section, the base of the triangle (anterior) being less 

 than the straight side. The horns are very much compressed towards the end, and terminate 

 in a rounded tip. These tips are 19^- inches apart, and distant eleven inches in a straight line 

 from the anterior base of the horn ; the ordinate of the arc, of which the straight line is the 

 chord, measures 8^ inches from the convexity of the horn. The orbits are appreciably larger. 



In the female the horns are much smaller, and more like those of a male goat not fully 

 grown. They are compressed laterally, the sides curved, and more flattened to the tip. They 



