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Alnus
949

in girth, being drawn up in a wood by other trees. It is growing on good loam over clay, and is the only big pole of the species in the wood; others which have been cut throw up many shoots from the stool, of which the majority die. On Lord Castletown’s property at Doneraile, Co. Cork, there is a wood,’ partly composed of grey alder, which has in places covered the ground with its suckers. (H.J.E.)

ALNUS CORDATA, Italian Alder

Alnus cordata, Desfontaines, Tabl. Hort. Paris, 244 (1815); Winkler, Betulaceæ, 110 (1904).
Alnus cordifolia, Tenore, Flor. Neap. i. Prod. p. xiv. (1811), and ii. 340 (1820); Loudon, Arb. et Frut. Brit, iii. 1689 (1838); Baillon, Nat. Hist. Plants, vi. 223, figs. 158–164 (1880); Masters, Gard. Chron. xix. 284 f. 42 (1883); Mathieu, Flore Forestière, 428 (1897).
Betula cordata, Loiseleur, Notice, 139 (1810), ex Loiseleur, Fl. Gall. ii. 317 (1828).

A tree, attaining 80 feet in height. Bark greyish-brown, smooth or slightly warty. Young branchlets, three-angled at the tip, stout, glabrous. Leaves (Plate 268, Fig. 4) about 4 inches long and 3 inches broad, oval or ovate, cordate at the base, shortly and abruptly acuminate at the apex; margin not lobulate, regularly serrate ; nerves six to ten pairs, looping before reaching the margin; upper surface dark green, shining, glabrous ; lower surface light green, glabrous, except for axil-tufts of rusty brown pubescence; petiole 1 to 2 inches, glabrous. Male catkins, three to four in a terminal raceme. Cones, solitary or two to three in an erect terminal raceme, I to 1¼ inches long, ovoid. Nutlet, sub-orbicular, with a thin narrow wing.

In winter the twigs are glabrous, with leaf-scars and stipule-scars like those of the common alder. Buds long-stalked, arising from the twigs at a wide angle, ovoid, beaked at the apex, glabrous and covered with wax glands; scales ciliate in margin.

Seedling * :—Cotyledons oblong-oval, slightly fleshy, pale green, about ⅓ inch long, with a very short grooved petiole. Caulicle pubescent, about ½ inch long, ending in a tapering flexuose tap-root. Young stem brown, pubescent. Leaves alternate ; first pair broadly ovate, acute or cuspidate, irregularly and acutely serrate, with pubescent petioles ; ultimate leaves cordate, cuspidate.

This species shows no variation in the wild state, except that the leaves are occasionally rounded and not acuminate at the apex. It differs considerably from A. subcordata, which has been supposed to be a variety of it; and is readily dis- tinguished from all other species by the conspicuous cordate base of the leaves.

Alnus elliptica, Requien, Ann. Sc. Nat. v. 381 (1825) is a remarkable natural hybrid between A. cordata and A. glutinosa, which was originally found growing on the banks of the river Salenzara in Corsica. It has leaves, similar in size to those of A. cordata, but thinner in texture, oval or elliptical, rounded at the base and apex ; margin not lobulate, finely and equally serrate; glabrous on both surfaces, except for axil-tufts beneath. The fruits are not so large as in A. cordata, and are inter-


1 Described by Prof. Fisher in Quarterly Journal of Forestry, ii. 95 (1908).

2 Cf. Lubbock, Seedlings, ii, 531, f. 666 (1892).