some little interest for those naturalists engaged in the study of the varied modes of fertilization in use among plants, I have drawn up the following notes on the subject.

Glossostigma elatinoides is a small, creeping, intricately branched mosslike plant, generally found in wet swamps, or by the margins of lakes and ponds, often growing entirely submerged. The flowers, which are axillary on short peduncles, are very minute, hardly exceeding ⅛ inch in diameter. The corolla has a short tube and five nearly equal spreading lobes; the two upper, however, are rather smaller and more closely united than the lower. The margins of all the lobes are fringed with numerous minute ciliæ, and the cellular tissue throughout is unusually lax. The stamens are four in number, two long and two short, the anthers being approximated in pairs, one above the other, as in so many of the Scrophularineœ. The style is about the same length as the corolla. At the base it is nearly cylindrical, and very slender, but above the middle it expands into a broad and thin spoon-shaped lamina, the anterior surface of which is quite smooth and plane, but the back covered with delicate clavate papillæ pointing upwards towards the summit of the style.

On examining a recently expanded flower, it will be observed that the broad end of the style is abruptly doubled over towards the front of the flower, thus covering the stamens and entirely concealing them from view. If the point of a needle, or stiff bristle, be inserted into the corolla, and the front of the stigma lightly touched, it at once springs up and uncovers the stamens, moving back to the upper lip of the flower, to which it becomes so closely applied that it is difficult to distinguish it from the corolla without the use of a lens. After a short time the style gradually moves inwards, and ultimately bends over the stamens as at first. With the view of ascertaining the time which elapses before the stigma resumes its normal position, I made the following experiment. At 9 a.m. I touched the stigmas of seven flowers, causing them to uncover the stamens and occupy their position at the back of the flower. At 9.12 one of the styles had commenced to move inwards; at 9.15 all had advanced a considerable distance; at 9.20 five out of the seven covered the anthers as closely as at first; at 9.25 the whole of the seven had resumed their original position. Further experiment also showed that the stigmas may be repeatedly touched, but always retain their sensitiveness until the flower commences to wither.

It cannot be doubted that this irritability of the style is connected with the fertilization of the plant—in fact, that it is solely a contrivance to secure cross-fertilization possibly so arranged that if the flower is not visited by insects self-fertilization is not prevented. Let an insect crawl into the flower, or let a larger one insert its proboscis; it would be difficult for either

to avoid touching the upper part of the style, which would then move back and expose the anthers. On retiring, the insect would in all probability dust itself over with pollen, but it would not by this effect the fertilization of the flower, as the stigma would then be closely applied to the upper lip of the corolla,—entirely out of its path. But let the same insect visit a second flower, and it is then every way likely that some of the pollen would be rubbed off by the stigma, which as we have seen, would be naturally touched on the first entrance of an insect. I have not been able to systematically watch the flowers so as to ascertain what species are instrumental in transferring the pollen, but I have twice observed small Diptera engaged in sucking the flowers. Several of these I caught, and found grains of pollen on the foreheads of some of them. The common red ant is often found crawling over the plant, and I have seen one emerge from a flower with the front of its head thickly covered with yellow pollen, thus proving that this species may play no unimportant part in the fertilization of the plant. Their visits would not, however, be so beneficial as those of winged insects, which would be more likely to bring pollen from distinct plants, and thus effect a more advantageous cross.

Late in autumn the plants are usually covered with capsules, so that, if fertilization is chiefly performed by insects, they certainly fulfil their duties in an effectual manner. In old flowers that have been seldom visited it often happens that pollen drops from the anther-cells on to the face of the style bent down just below; and I perhaps too hastily concluded that self-fertilization would thus inevitably take place if from any reason the flowers were not visited by insects. I did not, until almost too late in the season, pay sufficient attention to the difference existing between the two surfaces of the expanded portion of the style; and I am now inclined to believe that only one is stigmatiferous—the posterior one, or that turned to the back of the flower when the style is erect, and to the front when it is curved over the stamens. Certainly this surface alone possesses well-developed stigmatic papillæ, and on it alone have I been able to observe the development and intrusion of the pollen-tubes. If this view is correct, self-fertilization would be almost, if not altogether, impossible.

The movements of the style in Glossostigma form the most curious example of irritability in the female reproductive organs of plants that I am acquainted with, excepting that produced by a slight touch on the gynostemium of Stylidium. The closing together of the two arms of the style in Mimulus and allied genera is analogous; but in the case of these plants the movement is rarely through a greater angle than 60° or 7°, and is usually much less; while in Glossostigma the point of the style moves through an arc of at least 180°. On referring to the description given by