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It was Darwin who first pointed out that self-fertilisation was injurious in the long run, and this important fact we continually see confirmed by weighty evidence, not in the vegetable kingdom alone, but also in the animal world. I happened the other day to examine rather closely certain flowers of that somewhat uncommon greenhouse plant, Leschenaultia formosa, and was agreeably surprised to find it furnished with everything needed in order to insure the most perfect fertilisation of the stigma by pollen from its own flower, or, to speak more correctly, every provision is made for the pollen to become located in the stigmatic cavity of the style, although the production of perfect seed is not at all common by this plant, -a fact rather surprising to a superficial observer, since the most perfect arrangements are made for the pollen to become not only deposited, as I said before, but retained there very effectually by the peculiar construction of the stigma itself. In order to make myself fully understood a few figures will be necessary, and it will be as well to state at the commencement of my description that the pollen is shed by the anthers before the expansion of the flower, as is the case with many plants, those belonging to the Leguminosæ more especially.

When young, or in the unexpanded bud, the style is shorter than the five stamens, the anthers of which slightly cohere by their margins at this stage of their development, as is the case also in Composite plants.

At this time the mouth or stigmatic cavity of the style is open, as at I, fig. 255, which represents the style after it has forced its way up the tube formed by the coherent anthers, rupturing them until they only cohere by their apices. When the style has lengthened sufficiently to bring the apex, or stigma, in close continguity with the introse anthers, the latter shed their pollen, and from their peculiar position around the open stigma it is nearly impossible that any can escape, seeing that the anthers form a close basket, so to speak, round the apex of the style, and the whole being closely enveloped by the, as yet, unexpanded flowers. After the pollen is shed from the anthers the flowers expand, and the style elongates still more, but the mouth of the 2-lipped stigma becomes firmly closed, as shown at 2, but in every flower I examined (35) I found pollen located in these closed, box-like stigmas, as at 3, which shows one partly opened by force. The flowers themselves are irregular and tubular, the upper three lobes of the corolla being slightly reflexed, the two lower, which form the keel, are projected at a right line with the tube, and the style and stigma lie on these after the full expansion of the flowers. The lower position of the stigma is bearded, as shown in the figure (2, 3), and immediately above the hairy portion it is slightly glutinous. Now, looking at the above-mentioned facts, one is led to inquire how it is that a plant like the present-the flowers of which are invariably fertilised with their own pollen-cones to be comparatively barren. I myself have never seen seed produced, but a well-known plant-grower and horticulturist informs me he has obtained seed from it, but whether naturally or by artificial fertilisation with pollen from other flowers, I am not in a position at present to state with that degree of certainty requisite in inquiries of this description.

The question naturally enough arises. Has the plant degenerated and become sterile in consequence of this invariable self-fertilisation? If so, how can we account for the Leguminosae, most of which are naturally fertilised by pollen from their own flowers for they like the plant at present under consideration  in many cases shed their pollen before the corolla expands? Perhaps some of your numerous and intelligent readers can inform us if they have ever gathered perfect seed from Leschenaultia formosa. F. W. B.

(A very interesting case. Eds.)