iven us an incoherent abstract of
Colonel Smith's article on the _Bovinae_, without, however, making the
least attempt to verify the statements there recorded. The descriptions
and characteristics are avowedly Colonel Smith's; but, in justice to
the latter gentleman, it must be added, that the disquisitions on the
circular succession of forms, and the analogical relations, are entirely
Mr. Swainson's.

ON SPECIES AND VARIETY.

What constitutes a species? And how far do the limits of varieties
extend? Cuvier, who is, perhaps, the best authority we can have upon
this subject, in defining a species, says:--_A species comprehends all
the individuals which descend from each other or from a common
parentage, and those which resemble them as much as they do each other._
Thus, the different races which they have generated from them are
considered as varieties but of one species. Our observations, therefore,
respecting the differences between the ancestors and the descendants,
are the only rules by which we can judge on this subject; all other
considerations being merely hypothetical, and destitute of proof. Taking
the word _variety_ in this limited sense, we observe that the
differences which constitute this variety depend upon determinate
circumstances, and that their extent increases in proportion to the
intensity of the circumstances which occasion them.

Upon these principles it is obvious, that the most superficial
characters are the most variable. Thus colour depends much upon light;
thickness of hair upon heat; size upon abundance of food, &c. In wild
animals, however, these varieties are greatly limited by the natural
habits of the animal, which does not willingly migrate from the places
where it finds, in sufficient quantity, what is necessary for the
support of its species, and does not even extend its haunts to any great
distances, unless it also finds all these circumstances conjoined. Thus,
although the Wolf and the Fox inhabit all the climates from the torrid
to the frigid zone, we hardly find any other differences among them,
through the whole of that vast space, than a little more or less beauty
in their furs. The more savage animals, especially the carnivorous,
being confined within narrower limits, vary still less; and the only
difference between the Hyaena of Persia and that of Morocco, consists in
a thicker or a thinner mane.

Wild animals which subsist upon herbage, feel the influence of climate a
li