The horn is a straight, conical spike from 4 to 6 inches long, according
to age, and perfectly black. The legs are proportionally longer and
larger in the joints than those of the full-grown animal. The
countenance of the yearling is quite interesting. The sleepy, helpless,
innocent expression of the very young calf has given place to a
wide-awake, mischievous look, and he seems ready to break away and run
at a second's notice.

The measurements of the yearling in the Museum group are as follows:

+----------------------------------------------------------------+
|BISON AMERICANUS. (Male yearling, taken Oct. 31, 1886. Montana.)|
+----------------------------------------------------------------+
| (_No. 15694, National Museum collection._) |
+----------------------------------------------------------------+
| | Feet.| Inches. |
|Height at shoulders | 3 | 5 |
|Length, head and body to insertion of tail | 5 | |
|Depth of chest | 1 | 11 |
|Depth of flank | 1 | 1 |
|Girth behind fore leg | 4 | 3 |
|From base of horns around end of nose | 2 | 11/2 |
|Length of tail vertebræ | | 10 |
+----------------------------------------------------------------+

6. _The Spike Bull._--In hunters' parlance, the male buffalo between the
"yearling" age and four years is called a "spike" bull, in recognition
of the fact that up to the latter period the horn is a spike, either
perfectly straight, or with a curve near its base, and a straight point
the rest of the way up. The curve of the horn is generally hidden in