Of this fine Mesembryanthemum we have found no figure nor description. It is most allied to M. difforme, so well illustrated by Dillenius, and figured before by Plukenet; but the figure of Miller, _tab._ 126. _fig._ 2. quoted for the same plant in the four last editions of the _Species Plantarum_, is certainly M. dolabriforme, as the author himself says, although his editor here has not stuck close to his text. M. heterophyllum is very distinct from either, is a free growing species, and flowers from June to September, the blossom open early in the morning, and shut in the afternoon. It is propagated both by seeds and parting the roots. The fruit is divided into eight loculaments for the seed, separated longitudinally by double elastic partitions, which are reflected above, so that the edges come in contact together and cover the seeds. Eight elastic valves attached to the margin of the fruit, and adhering firmly to the part containing the seeds, and to one another until mature, again enclose these. Two cartilaginous coloured bodies, jointed near the base, and arising from the outer edge of the partitions, are prominent upon the interior of each of those valves, which have their edges always more or less reflected to facilitate the entrance of moisture to the seeds, above which they continue to lie close so long as the atmosphere continues dry: but, when it rains, or water is poured upon them, it enters by the openings between the valves, and is imbibed by the receptacles of the seeds and cartilaginous partitions, which presently become much dilated, and the diameter of the fruit is considerably increased. The upper valves also by this extension are drawn outwards, and being pressed at the same time by the edges of the partitions, resting against the elastic rigid bodies on their interior surface, gradually rise to be perpendicular upon the margin, when the fruit somewhat resembles a little cup with a Vandyke edge; but this is of short duration, as the less elastic and hygrometrical exterior of the valves (for their interior parts imbibe water and dilate rapidly) soon draws them backwards into the form of a star or polypetalous flower, with colours as vivid as if really vegetating. The edges of the partitions now become more erect, leaving the seeds uncovered; and the water being led towards the centre by channels in the valves, and retained by an elevated margin, the seeds are floated out of their cells. The fruit when dry, again contracts as before, and the experiment may be repeated _ad libitum_. What a wonderful œconomy of Nature to produce the seeds just at the moment proper for their germination, and preventing them until that time from falling on the parched sands and rocks upon which those plants vegetate! In some plants, natives of cold regions, where seeds are in danger of perishing by moisture, and there is seldom sufficient warmth for their vegetation, an œconomy the direct reverse takes place. The cones of pines, being