164 TRICHOLOGIA MAMMALIUM : 
ment more fully than I have, but with the same result. Lam perfectly satisfied that the 
fine woolled Sheep [the woolly Sheep] and the Goat m/l not mix. 1 know of no case 
where it has been tried with the coarse hairy Sheep.” 
From all that has been said, we feel warranted in believing that the best rule we possess 
of discriminating between species, is to inquire whether Nature has thrown any impedi- 
ment between the animals to /ree sexual intercourse, and whether the progeny form a 
permanent, self-supporting race of animals, which cherit equally the properties of both 
parents. And we feel confident that a trial of the hairy Sheep and the woolly Sheep, by 
this law, in order to ascertain whether they are one and the same, or two distinct species, 
will result entirely in favor of the ground we have taken. 
The reader will be so good as to remark that we do not admit, as proof of belonging to 
the same species, that animals, either domesticated or wild, will mix together—nor that 
they will have progeny incapable of continuing the breed—nor that they will have progeny 
capable of continuing the breed for a limited time, after which a new draft must be made 
upon one of the original parents to prevent the breed from running out—nor where they 
have progeny capable of continuing the breed for a limited time, after which it runs out for 
want of power to continue it; but we admit, as proof of belonging to the same species, a 
breed where nature has thrown no impediment in the way of free sexual intercourse, and 
where the progeny constitute a permanent, self-supporting race, partaking equally of the 
properties of doth parents. 
Mr. Youatt, when speaking of the attempt, in England, to amalgamate the Southdown 
Sheep (which is itself a hybrid, being a mixture of the hairy and the woolly species,) with 
the Leicester Sheep, (which belongs to the hairy species,) pronounces it “A FAILURE.” 
And he adds, that ‘the promised advantages to be derived lrom the mixture of the South- 
down with the Merinos, “WERE DELUSIVE.”” (See Essay on Sheep, p. 233.) 
It is true that this author does not appear to be aware of the cause. of this fatlure, nor 
of the reason why the expectations, to which he has referred, were delusive; but he has 
furnished us with the facts, and the inferences to. be adduced from them are irresistible. 
Doctor Robert Knox, an English lecturer on anatomy, and corresponding member of 
the National Academy of Medicine, in France, in a recent work upon the Races of Men, 
(52,) says: ‘The theories put forth, from time to time, of the production of a new 
variety, permanent and self-supporting, independent of any drafts or supphes from the 
pure breeds, have been distinctly disproved. It holds neither in Sheep nor Cattle; and 
again, (in page 68:) ‘But the statement in question is not even true of Sheep; for by 
no effort, saving that of constant, never-ceasing intermixture, or draughts on the pure 
breeds, can a mixed breed be maintained.” 
So, Col. Randall (in Sheep Husbandry in the South, p. 170,) admits, that any attempt 
to wnite the Merinos and the Leicesters, by crosses, IS AN UNQUALIFIED ABSURDITY. 
It is true that this last gentleman, (incautiously, as we presume,) advises the crossing 
of the Southdown and the Merino ; but such crossing of a hybrid, formed from an amal- 
gamation of the two species, with the pure race, of one of the species, is no less an 
“unqualified absurdity,” although the reason may not, at first, be quite so apparent to 
every one. 
