e in accordance with the rule above indicated, i.e.
the male gives mostly the outward form and locomotive system, and the
female chiefly the interior system, constitution, &c. Where the
parents are of the same breed, it appears that the portions
contributed by each are governed in large measure by the condition of
each in regard to age and vigor, or by virtue of individual potency or
superiority of physical endowment.

This _potency_ or power of transmission seems to be legitimately
connected with high breeding, or the concentration of fixed qualities
obtained by continued descent for many generations from such only as
possess in the highest degree the qualities desired. On the other hand
it must be admitted that there are exceptional cases not easily
accounted for upon any theory, and it seems not improbable that in
these the modifying influences may be such as to effect what may
approximate a reconstruction or new combination of the elements, in a
manner analogous to the chemical changes which we know take place in
the constituents of vegetables, as for instance, we find that sugar,
gum and starch, substances quite unlike in their appearance and uses,
are yet formed from the same elements and in nearly or precisely the
same proportions, by a chemistry which we have not yet fathomed.
Whether this supposition be correct or not, there is little doubt that
if we understood fully all the influences at work, and could estimate
fairly all the data to judge from, we might predict with confidence
what would be the characteristics of the progeny from any given union.

Practically, the knowledge obtained dictates in a most emphatic manner
that every stock-grower use his utmost endeavor to obtain the services
of the best sires; that is, _the best for the end and purposes in
view_--that he depend chiefly on the sire for outward form and
symmetry--that he select dams best calculated to develop the good
qualities of the male, depending chiefly upon these for freedom from
internal disease, for hardihood, constitution, and generally for all
qualities dependent upon the vital or nutritive system.

The neglect which is too common, and especially in breeding horses, to
the qualities of the dam, miserably old and inferior females being
often employed, cannot be too strongly censured. In rearing valuable
horses the dams are not of less consequence than the sires, although
their influence upon the progeny be not the same. This is well
un