on of the Indian Ox (Gardens and Menag. of the Zool. Soc.), may
be taken as a correct exposition of the views of naturalists generally
on the subject:--

"There can be little doubt that the Zebu, or Indian Ox, is merely a
variety of the Common Ox, although it is difficult to ascertain the
causes by which the distinctive characters of the two races have been in
the process of time gradually produced. But whatever the causes may
have been, their effects rapidly disappear by the intermixture of the
breeds, and are entirely lost at the end of a few generations. This
intermixture and its results would alone furnish a sufficient proof of
identity of origin; which, consequently, scarcely requires the
confirmation to be derived from the perfect agreement of their internal
structure, and of all the more essential particulars of their external
confirmation. These, however, are not wanting; not only is their
anatomical structure the same, but the form of their heads, which
affords the only certain means of distinguishing the actual species of
this genus from each other, presents no difference whatever. In both the
forehead is flat, or more properly slightly depressed; nearly square in
its outline, its height being equal to its breadth; and bounded above by
a prominent line, forming an angular protuberance, passing directly
across the skull between the bases of the horns. The only circumstances
in fact in which the two animals differ, consists in the fatty hump on
the shoulders of the Zebu, and in the somewhat more slender and delicate
make of its legs."

In a scientific work, it is not sufficient for the author merely to make
an assertion; it is not even sufficient for him to say that he has made
an experiment or observation, and merely give the result; he should, in
every case where it is practicable, describe the nature of his
experiment,--the _when_, the _where_, the _how_;--and the means and
opportunity he had of making his observations, that the curious or
sceptical inquirer may be enabled to perform the experiment, or make the
observation for himself.

Mr. Bennett tells us, that the differences observable in the Indian Ox
and the Common Ox "_rapidly_ disappear by the intermixture of the
breeds, and are entirely lost at the end of a few generations;" but he
does not refer to a single instance of this, authentic or otherwise; nor
are we aware that any such instance ever occurred.

Again, he states that "their anatomical st