Page:Transactions of the Linnean Society of London, Volume 12.djvu/428

posed species of each of the preceding genera would, I am very confident, be found capable of breeding with, and being transmuted into, each other, as to their external characters; and if botanical writers still choose to call such species, they ought certainly to distinguish them from others, as secondary or transmutable species. The external form and character of each plant, as it came from the hand of nature, was probably sufficiently peculiar to render it readily distinguishable from those of every other species: but varieties of soil, of climate, and of culture applied for other purposes, have so far mixed and confounded the primary characteristics of many species, that experiments, such as those above described, now afford probably the only source of decisive evidence.