NOTE ON THE AMERICAN BISON.
It was Cuvier, I believe, who first made the statement, that the American Bison is furnished with fifteen pairs of ribs. In this particular he has been implicitly followed by every subsequent writer on the subject. Not being able to refer to a skeleton, and, moreover, never suspecting any inaccuracy in the statement, I followed the received account. But since this work has gone to press, I have had the opportunity of examining two skeletons, by which I find that—
The American Bison has only fourteen pairs of ribs.
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.'