Another plant, like an aloe in appearance, called _tarètra_ (_Fourcroya gigantea_) by the natives, has long leaves, with a sharp spine at the ends only; and its flower-stalk shoots up like a small mast to a height of twenty feet, with widely spreading branchlets and an immense number of light coloured flowers. Strong fibre used as thread is obtained from the leaves, the name of the plant being indeed that used for “thread.” The tall flower-stalks of these aloes and agaves form quite a noticeable feature in the Imèrina landscape in the early summer. In the orchards, soon after the mango has finished flowering, we may see the curious whitish flowers of the rose-apple, a sort of ball of long stamens, showing conspicuously among the foliage. [Sidenote: WATER-PRODUCING INSECTS] It is well known by those who live in Madagascar that there are, at certain seasons of the year, a number of insects found on trees which produce a constant dropping of water. Happening one day to be standing under a peach-tree in our garden from which water was dropping, I found that there were clusters of insects on some of the smaller branches. In each cluster there were about twenty to thirty insects, and these were partly covered with froth, from which the water came. The insects producing this appeared at first sight to be small beetles, about half-an-inch long, black in colour, with golden-yellow markings on the head and thorax, while on the wing-cases there was a chequer of minute spots of yellow on the black ground. After observing a single insect for a few seconds, I noticed that the tail was quite flexible and moved sideways, and was constantly protruded and then withdrawn a little, and it was evident that these little creatures were the larval form of a species of beetle. The sap of the tree is extracted in such quantities as to maintain their bodies in a state of saturated humidity. The activity of the larvæ seems to increase as the heat of the day progresses, and to diminish again towards evening. But the object of this abstraction of fluid from the tree, and the purpose it serves, is still a subject needing investigation. I have observed these insects on other trees—mangoes, acacia, _zàhana_, and others; they appear indeed to be very common, and the ground underneath the branches where they cluster is covered with small patches soaked with water. A French naturalist, M. Goudot, described an insect apparently of the same kind as that found in Imèrina as the larva of a species of _Cercopis_, and nearly related to the cicada of Europe. The quantity of water produced from a tree at Tamatave seems to have been much greater than that observed in the interior, and resembling a small rain-shower; probably this was due to the greater heat of the coast. M. Goudot says that the perfect insect attains a length of an inch and a half, and that these also emit small drops of clear and limpid water.