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Grammatophyllum (From grammata letters)

(from grammata, letters, and phyllon, a leaf; in reference to the markings on the leaves). ORD. Orchideoe. A genus of three or four species of rather large-growing, handsome stove epiphytal orchids, usually very shy of flowering. All are natives of the Malayan Peninsula and Archipelago. Grammatophyllums should be cultivated in large pots, filled with peat. Good drainage and a liberal supply of water, when the plants are in a growing state, are essential elements in their culture. After a few strong growths have been made, the plants should be allowed a season of rest. Propagated by divisions of the pseudo-bulbs. The under-mentioned are the only species in general cultivation, and these are still very rare.

G. multiflorum (many-flowered).* fl. green, brown, purple; racemes long, many-flowered; bracts oblong, scale-formed; sepals downy; middle lobe oblong, rounded; lateral ones erect, sub-falcate, with four elevated lamellae in middle. Summer. l. linear, distichous, striated. h. 2ft. Manilla, 1838. (B. R. 1839, 65).

G. m. tigrinum (tiger-spotted). fl. yellow, spotted with purple. Summer. h. 2ft. East Indies, 1840. (B. R. 1842, 69.) G. speciosum (showy).* fl. nearly 6in. across; sepals and petals undulated, ovate-oblong, rich golden-yellow, spotted with purple; lip three-lobed, streaked with red; scape often nearly 6ft. long, growing from the base of the stem. Winter. l. distichous, lorate, acute, 1 1/2ft.to 2ft. long. Stems sometimes 9ft. to 10ft. high. Java, 1837. One of the most elegant plant in cultivation. (B. M. 5157.) GRAPE OR VINE LOUSE (Phylloxera vastatrix). This insect belongs to the Aphides, or Green Flies, a group that contains many species very destructive to field and garden crops, but none which approaches this in the injuries done by it. The insect lives on the European Vine (Vitis vinifera), forming galls on both roots and leaves; and, when it has once effected a settlement, the plant, if left to itself, soon perishes under the attacks. The injuries to the leaves are of comparatively slight moment; the danger proceeds from the effects produced on the young roots. The insects frequently affix themselves near the tips of newly-formed roots, and push their probosces through the bark, it may be even to the cambium. There results from this a thickening of the bark, due to the development of new cells-hence the formation of galls, some of which reach the size of a the size of a pea; and, after a time, the central part of the root also becomes modified. In autumn, the healthy young roots begin to undergo enlargement, to form the older ones of the next year; but, in those affected, the galls die, and the roots also perish. The plants are thus deprived of due nourishment, and are starved; while, at the same time, they are weakened by the abstraction of food by the insects on the older roots and leaves. Phylloxera vastatrix passes the winter on the roots. In spring, the plants push out young branches and leaves, but these soon become yellow, and wither; and the fruit, if they ripen, often remain uncoloured and sour. The next year, the leaves are still more deformed; and fruits are not formed, or do not ripen. The insects leave the Vines before the latter are quite dead, and crawl about in search of new plants. Hence, any diseased plant is a dangerous centre of infection in a vinery. The insects vary in appearance. Eggs laid, in the autumn, between the crevices of the bark on the roots, produce, in spring, larvae, which pass, with little change, except mere increase in size, into the mature females. These larvae usually form galls on the leaves, but, at times, the roots alone are attacked. The leaf-galls form small reddish warts on the one surface of the leaf, with small depressions on the other surface. In this depression is the entrance to the gall a slit, closed with hairs. From the leaf-galls emerge wingless insects, which continue for a time to form new galls, and at last pass down to the roots. In fig 147, A shows sketch of a Vine root attacked by phylloxera; B, portion of leaf of Vine, showing the galls formed on the leaf by the Phylloxera, as seen both on upper and under side; and c, subterranean form of female, magnified. The eggs are about 1/80in. long. The mature female may reach 1/30in. length, and varies in colour from pale yellow to dull brown. The males become winged when mature; the body is about 1/40in. or 1/50in. long; the wings are nearly twice as long as the body. The colour is golden-yellow, or approaches dull orange, except a dark band across the thorax. The eyes are red in both sexes.

History. The disease of Vines caused by Phylloxera was first noticed in 1863, in Southern France, but did not seem very dangerous till 1865. Planchon, in 1868, discovered that it was caused by the insect, which, however, had been previously known to zoologists. In 1856, Dr. Asa Fitch observed it in America, and named it Pemphigus vitifoliae. In 1863, it was discovered in vineries near London, and was named by Professor Westwood Peritymbia vitisana. In France, it spread very rapidly, even till it reached the most northern vineyards. In the department of Vaucluse, the yield of wine had, in 1876, been reduced to about one-tenth of the former amount. The disease still spreads, and has appeared in most countries of Western and Central Europe.

The effect of the legislation which the dread of the Phylloxera has brought about, seriously interferes with the nurserymen who export plants. In some countries Germany, for example-no plants are allowed to be imported. An exception in this case, we believe, is made in favour of "bulbs;" but plants equally unlikely to be in any way the means of furthering the spread of the Phylloxera, are rigidly refused admission. In order to send plants to any of the countries in which the regulations of the Phylloxera Convention are enforced, it is necessary to sign a declaration that the package contains no Vines or roots of Vines, that no Vines are grown near the place whence the plants were taken, and that no Phylloxera exists, or has existed, in the immediate neighbourhood. This declaration must be stamped and countersigned by a magistrate, and afterwards be presented to the Consul or Vice-Consul of the country to which it is proposed to send the package, for his vise. The fee for the latter varies almost for every country. The declaration is then handed to the agent or railway company who undertake to forward the plants: without it, the goods are not allowed to be sent to their destination. Remedies. These fall almost entirely under the head of "Prevention of the Spread of Disease," which has been attempted in various countries by strict prohibition of the export of Vines from infected districts, and of the import of Vines into places where disease has not yet appeared (the German law of 11th Feb., 1873, is especially strict in this matter). It has also been attempted by the destruction of the Vines wherever disease has appeared. The German law of 6th March, 1875, enforces the thorough uprooting of infected plants, burning every part, and a disinfection of the soil, for which many substances have been used-the most reliable, however, is carbon disulphide, which destroys the insects on the roots, but does not injure the plants, especially if applied in winter. A mixture of carbon disulphide and coal-tar has also been advised; and a good mode of using it is to scatter on the soil pieces of wood saturated in the mixture, and washed with water-glass (silicate of potash), so as to allow the gases to pass off gradually as the latter dissolves. Another method is, where easily practicable, to lay the soil under water for six or seven weeks. The American Grape Vines, especially V. cordifolia and V. aestivalis, resist the attacks of Phylloxera far better than do the European species; and, of late years, they have been largely introduced into European vineyards, for the purpose of supplying stocks on which to graft the better flavoured, but more delicate, Old World varieties. ("Enquete de l'Academie des Sciences sur le Phylloxera." Paris, 1879. 2vols., with many plates.)