» 
210 Remarks on Hybridity. 
is particularly “peer <4 the admirable essays of the Rev. Mr. 
Herbert, and M. 8 
e may remark, Samak that so abundant are these hybrids, 
that Mr. Herbert, in order to avoid the difficulty they present to 
a favorite theory, declares it as his opinion, that botanical species 
are only a higher and more permanent class of varieties, which 
should be discarded from the — leaving the genera to de- 
‘ fine the individuality of kind; or, in other words, to designate 
those anent characteristics, wie have hitherto, in his opin- 
ion, been erroneously attributed to species. t 
But i in the treatise of M. Sagaret, various instances are given of 
hybrid plants derived from the mixture of different genera; thus 
realizing, in this department of nature, the same facts that we 
have seen to occur in the several sections of the zoological series. 
We will offer a single example,—the cross horse- 
radish (Cochlearia raphanus) and the cabbage ; the former bear- 
ing a short pod, or szdicula, the latter a long pod or szliqua. 
Remarks. 
While we admit that hybrids, as a general law, are contrary to 
nature, we are also compelled to concede that this law has very 
many exceptions. “It is manifest,” says Dr. Prichard, “ that there 
is some principle in nature which prevents the intermixture of 
confusion. By what method is this confusion prevented? ‘The 
fact seems to be, that the tribes of wild animals are preserved dis- 
tinct, not only by the sterility of mules, but that such animals 
are never, in the state of nature, brought into existence. The 
separation of distinct species is. sufficiently provided for by the 
natural repugnance between individuals of different kinds. This 
is, indeed, overcome in the state of domestication, in which the 
fa propensities cease, in a great measure, to direct their ac- 
tions.’ 
But we have seen that mules are not always sterile, and also 
that hybrids are really produced in a state of nature, wholly in- 
dependent of the influence of cultivation ; facts which, indeed, 
are admitted and illustrated by Dr. Prichard in his later ‘writings. 
That domestication evolves the faculty of hybridity there can be 
no question; and we would ap ly the principle to various classes 
of animals. It will materially assist in explaining so great a vari- 
ety in some animals, by pointing, as De Azara and Hamilton Smith | 
* Herbert. Amaryllidacee. sate _ agaret. Annales des Sciences Nat. 
T. viii. Awary dasa ez, p. 19. 
$ Researches into the Physical dtactnay of Mankind, i, p. 97. Second Edition. 
