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OF GENERA AND

for a limited time, if at all, perpetuated in the offspring.

A Genus comprehends one or more species, so essentially different in formation, nature, and often many adventitious qualities, from other plants, as to constitute a distinct family or kind, no less permanent, and founded in the immutable laws of the creation, than the different species of such a genus. Thus in the animal kingdom, a horse, ass and zebra form three species of a very distinct genus, marked, not only by its general habit or aspect, its uses and qualities, but also by essential characters in its teeth, hoofs, and internal constitution. The lion, tiger, leopard, panther, lynx, cat, &c., also compose another sufficiently obvious and natural genus, and the numerous herd of monkeys, apes and baboons a third. The elephant is, as far as we know, a solitary species of a most distinct and striking genus.

So among vegetables, the various species of rose compose a beautiful genus, known to every one who ever looked at a plant, merely by a certain combination of ideas, but essentially distinguished, as we shall hereafter find,