Page:TheTreesOfGreatBritainAndIreland vol04B.djvu/273

great variation, but that no special form can be singled out as deserving the name rotundifolia; and I have seen no specimens of F. Ornus, which could be separated as a var. rotundifolia, much less any which could be separated as a distinct species.

A variegated form of F. Ornus, of which I have seen no specimens, is said to occur in cultivation. A simple-leaved form, var. diversifolia, Roch., is of rare occurrence in the wild state, and has been noticed in the canton of Tessin in Switzerland.’

The manna ash is widely distributed in southern Europe and Asia Minor. In France it only occurs wild in the department of the Maritime Alps; and in Switzer- land it is met with in a few places in mountain woods about Lake Lugano in the canton of Tessin.” It grows in the southern Tyrol, where it ascends to 2000 feet elevation, in Carniola, Istria, Dalmatia, Croatia, Slavonia, and Banat, reaching its northern limit in Hungary on the south side of the Carpathian chain. It is common in eastern Spain, Corsica, Sardinia, Italy, Servia, Bosnia, Greece, and Asia Minor.

The wood of the flowering ash is excellent, and the foliage is used as fodder in the southern countries of Europe; but its chief economic importance is due to its being the source of manna. The manna of commerce, according to Hanbury, is exclusively collected in Sicily, where the plantations are known as Frassinetti. However, of late years, attempts have been made to cultivate it on a large scale for manna in the southern parts of the Austrian empire. In Sicily trees begin to produce manna when they are about eight years old; and they are tapped in subsequent years annually until they are about twenty years old, when they are cut down and their place taken by coppice shoots from the stools. During July and August transverse incisions are made in the bark, so as just to reach the wood; and the manna exudes as a clear liquid, which solidifies on the stem of the tree or on pieces of straw or wood that are inserted in the incisions. Manna consists mainly of a peculiar sugar called mannite, which is a mild laxative and is employed as an officinal drug in many countries. (A.H.)

The manna ash is said to have been introduced into England by Dr. Uvedale of Enfield about 1710. It is commonly cultivated as an ornamental tree, on account of its beautiful appearance when in flower; and it thrives and attains a large size, especially in the southern parts of England. The largest I have measured is an old

1 Tenore, in Syll. Pl. Fl. Neap. 10 (1831) considers Lamarck’s plant to be a variety of F. Ornus. Both Tenore and Bertolini, Fl. Italica, i. 54 (1833), were of opinion that F. rotundifolia, Willdenow, was a distinct species. Lingelsheim, in Engler, Bot. Jahrb. xl. 212, 213 (1907), retains F. rotundifolia, Tenore, loc. ctt., as a distinct species, confined to a small area in south Tyrol, Bosnia, and Dalmatia ; and creates a new species, F. cilicica, occurring in Cilicia in Asia Minor. These supposed species appear to be glabrous forms of F. Ornus.

2 Cf. Bettelini, Flora Legnosa del Sottoceneri, 145 (1904).