I have, therefore, in the "Table of the Number of Vertebræ," (see p. 152,) set this species down as possessing only that number.
Of the two skeletons referred to (both of which are now in the British Museum), one is from a female Bison, some years a living resident in the Zoological Gardens; and the other is from a male, late in the possession of the Earl of Derby, at Knowsley, in Lancashire.
A corroborative circumstance (amounting, indeed, to a complete proof of the accuracy of these observations,) is presented by the fact, that, in both the cases the number of lumbar vertebræ is precisely five; thus making the true vertebræ to consist of nineteen, which Professor Owen[E] has shown to be the invariable number possessed by all ruminants.
FOOTNOTES:
[E] See, in the Proceedings of the Zoological Society, Professor Owen's 'Account of his Dissection of the Aurochs.'
APPENDIX
THE FREE MARTIN.
Cows usually bring forth but one calf at a birth; occasionally, however, they produce twins. John Hunter, in his 'Observations on the Animal Economy,' says: "It is a fact known, and I believe almost universally understood, that when a cow brings forth two calves, one of them a bull-calf, and the other to appearance a cow, that the cow-calf is unfit for propagation; but the bull-calf grows up into a very proper bull. Such a cow-calf is called, in this country, a Free Martin, and is commonly as well known among the farmers as either cow or bull. It has all the external marks of a cow-calf, namely, the teats, and the external female parts, called by farmers the bearing. It does not show the least inclination for the bull, nor does the bull ever take the least notice of it. In form it very much resembles the Ox, or spayed heifer, being considerably larger than either the bull or the cow, having the horns very similar to the horns of an Ox. The bellow of the Free Martin is similar to that of an Ox, having more resemblance to that of the cow than that of the bull."