. The natural history of plants, their forms, growth, reproduction, and distribution;. Botany. DISPERSAL BY WATER. 845 suppose that rain-water running off the plants and then trickling along the ground would be a very effectual means of dispersing fruits and seeds, but closer observa- tion convinces one that distribution is comparatively seldom effected in this manner, and that wherever such dispersion does occur it is invariably supplemented by some other means of dissemination. The best-known instances are afforded by two plants which, on account of their extraordinary properties, were broug
. The natural history of plants, their forms, growth, reproduction, and distribution;. Botany. DISPERSAL BY WATER. 845 suppose that rain-water running off the plants and then trickling along the ground would be a very effectual means of dispersing fruits and seeds, but closer observa- tion convinces one that distribution is comparatively seldom effected in this manner, and that wherever such dispersion does occur it is invariably supplemented by some other means of dissemination. The best-known instances are afforded by two plants which, on account of their extraordinary properties, were brought to Europe from the East by pilgrims and crusaders in the Middle Ages. They were called " Eoses of Jericho", and all sorts of marvellous tales were told concerning them. One of these plants is Anastatica Hierochuntica, a Crueifer which grows on the Steppe- lands of Egypt, Arabia, and Syria, and which has the peculiarity that its branches. Fig. 463.—Fruits wiiicli open upon being wetted with w iL e 1 Anastatica Sierochunfica, dry. 2 The same when wetted. 3 Fruit of Mesembryanthemum CaTutolleanwm, dry. * The same when wetted. 6 Fruit of MesembryantJtemum annuum, dry. 6 The same after being wetted. curve inwards when the fruits are ripe in such a manner as to form a trellis round the closed, pear-shaped siliquas, which are very numerous and are situated at the extremities of the ramifications, and to protect them from being touched (see fig. 463 ^). The shape of the structure in this condition is something like that of an unopened rose, and it remains unaltered so long as it keeps dry. When moistened the branches at once open back and stretch straight out (see fig. 463 ^). The fruits also open at the same time, and the seeds are then liable to be washed out of the fruit-valves by falling rain. When growing wild Anastatica remains closed during the long drought which follows the maturation of the fruits, and it is not till the winter rains set in that the tangle of br
Size: 2268px × 1102px
Photo credit: © Central Historic Books / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1890, booksubjectbotany, bookyear1895
