barbatum, of which a leaf is figured in the Penny Cyclopedia, and several in our fig. 125. p. 452., may possibly be only a variety of A. Pseudo-Plátanus, diminished in all its parts. A. coriàceum, which we consider as a synonyme of A. O'palus, and which, in the Penny Cycl., is considered a synonyme of A. créticum, may be a more distinct sort than we think it is, from having seen only small plants of it. These small plants have leaves as nearly as possible of the same form as those of A. Opalus, exhibited in fig. 126. p. 453.; and, therefore, the A. coriàceum mentioned in the Penny Cycl. as a synonyme of A.créticum, must refer to a different plant from the specimen of A. coriàceum in Loddiges's arboretum. A. Lobèlü Tenore, of which there is a tree, 20 ft. high, at Croome, in Worcestershire, certainly appears very distinct from A. platanöides (of which we have set it down as a variety) in the foliage of the plants about 2 ft high in the London nurseries; but not so in the specimens which we have received from Croome. A. nìgrum, which we consider as a variety of A. sacchárinum, ought to be proved by raising plants from seeds, which can be procured from America at the same price as those of A. saccharinum. It would not surprise us if A. platanöìdes and A. sacchárinum were ultimately to turn out to be races of one and the same species. Under the name of A. hybridum, it is probable that there is more than one variety or species in cultivation. The 4. hybridum of Bosc, with coriaceous leaves, profoundly trifid, seems to be different from the A. hybridum of Baudrillart, which he describes as intermediate between A. monspessulanum and A. tatáricum. In Don's Miller, there is A. obtusifòlium Flor. Græc., t. 361., a native of Crete; and there is also A. obtusàtum Kit., a native of Hungary: these may possibly be names applicable to one and the same species. A. lobàtum Don's Miller, i. p. 651., a native of Siberia, and said to have been introduced in 1820, is there designated an "extremely doubtful" species. App. ii. Anticipated Species of A`cer. All the species of this family are so interesting and ornamental, that it is desirable to procure additions to those already introduced into Britain, from every quarter of the globe, and by every resource which art supplies. It appears, from Don's Miller and Royle's Illustrations, that there are one or two European species, one from N. America, several from the Himalayas, and some from Japan, all likely to prove hardy, which are at present wanting in British collections. We shall give the names of these, in the hope of directing to them the attention of travellers, collectors, and patriotic amateurs. A. ibéricum Bieb., a tree 20 ft. high, native of Iberia, with greenish yellow flowers, and shining 3-lobed leaves, is described in Bieberstein's Flora Taurico-Caucasica, vol. ii. p. 447.; in Dec. Prod., i. p. 594.; and in Don's Mill., 1. p. 649. A. obtusifolium Sibth. and Smith, a native of Crete, a tree 15 ft. high, with 3-lobed crenated leaves, is described in the Flora Græca, and in Don's Mill.; in the latter work it is mentioned as being of doubtful introduction. A. parvifolium Tausch is described as having 5-lobed leaves, and nodding corymbs of flowers. It is a native of the south of Europe, growing to the height of 20 ft., by some confounded with A. créticum, and by others with A. monspessulanum. A. glabrum Torrey has smooth roundish 5-lobed leaves, and is found in North America, on the Rocky Mountains. Very little appears to be known of this species. A. lævigatum Wall has oblong, acuminated, smooth, shining, leaves, and white flowers. It is a native of Nepal, on high mountains, where it forms a tree 40 ft. high. It is described and figured by Dr. Wallich in his Plant. Asiat. rar., 2. p. 3. t. 104. A. acuminatum Wall., a tree of Nepal, with leaves varying from 3-lobed to 5-lobed, is described in Don's Prod. Fl. Nep., p. 249. A. cultratum Wall., a tree of Himalaya, with cordate, 7-lobed, acuminated leaves, is described by Wallich in his Planta Asiatica rariores, vol. ii. p. 4. A. caudatum Wall., a tree from the highest regions of Nepal, with long pointed leaves, is described in the work last quoted, vol. ii. p. 4., and in Don's Mill., i. p. 648. A. villòsum Wall., a tree 50 ft. high, native of the high alps of the Himalaya, near to perpetual snow, has cordate 5-lobed leaves, and fragant flowers. It is described in Dr. Wallich's work, and in Don's Mill., as before quoted. A. sterculiàceum Wall., is a tree 50 ft. high, with a trunk 3 ft. in diameter. The leaves are very large, with long petioles, and the flowers are white. It is found in Nepal, on Mount Shiopore. A. dissectum 'Thun. is a tree of Japan, with leaves 9-10-parted, and oblong acuminated lobes, with a red corolla. It is described by Thunberg in his Flora Japonica, p. 160.; in Dec. Prod., i. p. 955.; and Don's Mill., i. p. 650. H H A. japonicum Thun., with roundish palmate leaves, is a Japan tree, 20 ft. high, with the bark of the branches, and the corollas purple, and the fruit woolly. It is described in Thunberg's Flora Japonica, p. 161. ; in Dec. Prod., i. p. 595.; and in Don's Mill., i. p. 650. A. septentlobum Thun., with smooth, acuminated, 7-lobed leaves, is a Japan tree, 40ft. high, described by Thunberg, and, after him, by De Candolle and G. Don, as before quoted. A. pictum Thun., with smooth, palmate, 7-lobed leaves, is a Japan tree, 30 ft. high, with ashcoloured branches, and leaves variegated with white. Described as above. A. trifidum Thun., with undivided and trifid entire leaves, and twigs smooth and purplish, is a Japan tree, 20 ft. high, described in the works quoted. YA. truncatum, described in Bunge's List of Plants of the North of China, noticed in p. 176. New Sorts from Cross-Fecundation. A. obtusàtum has very much the appearance of a hybrid between A. Pseudo-Plátanus and A. O'palus; but, whether this be the case or not, there seems no reason for doubting that cross-fecundation might be effected in this genus, as well as it is in various others. The objects ought to be, to get more colour into the flowers, and more red into the leaves. A. monspessulanum, with flowers as red as those of A. rùbrum, would be a fine variety. Possibly some of the species might be fecundated by some species of the genus Negúndo, which would lead to great changes in the leaves. As a number of the species of Acer do not flower and perfect seeds, till they become considerable trees, it would be desirable, when experiments are to be made by cross-fecundation, and the person wishing to try these experiments possesses only young trees, to graft them with scions from trees which already flower and fruit. In collecting species for this purpose, care must be taken, either to procure plants producing hermaphrodite flowers, or plants having male and female flowers on the same tree; unless, indeed, advantage is proposed to be taken of the circumstance of the tree being only of one sex, to fecundate its flowers, if female, or pistilliferous, with the male flowers of another species; or, if staminiferous, to fecundate with them the female flowers of some other kind. We are strongly inclined to believe that some of what are now considered aboriginal species of Acer are only the result of cross-fecundation, produced by accident; and hence we anticipate a number of new forms, when the attention of cultivators is powerfully directed to this object. Negundo fraxinifòlium will, in all probability, fecundate, and be fecundated by, acers of different kinds; and this alone would produce something which would amply repay the curious cultivator. The tree produces flowers at an early age; and, as there are in almost every part of the country abundance of trees of Acer campestris, and A. Pseudo-Plátanus, which flower every year, we would recommend a trial to be made between these sorts without delay. Success may not attend the first trial, but the object ought to be persisted in till some result be obtained. A. créticum, A. monspessulanum, and A. campestre will, doubtless, fertilise together; because, in foliage, in mode of growth, in time of flowering, and in the form of the fruit, they are very much alike; and something might be done with them with very little trouble. Additional Sorts from accidental Forms of Growth. The eagle's claw maple is a well known and very curious variety. Whenever any appearance of the same kind is observed in any of the other species, it ought to be continued by grafting. By carefully looking out for sports from the average forms, we shall probably, at some future day, have weeping maples, as well as the weeping ash; fastigiate maples, like the Lombardy poplar; and purpleleaved kinds, like the purple-leaved beech or common hazel. Though scarcely any of the variegated maples now known can be considered as very handsome, yet a new and beautiful variety of them may one day be procured. App. iii. Half-hardy Species of A`cer. A. palmatum Thun., described p.422., is, in all probability, only half-hardy; or, at all events, it is safe to treat this, and the other Japan species, and also those from Nepal, when once they are pro cured, as half-hardy, when in their young state. 4. oblongum, described in p. 405, according to Mr. Royle, descends to the lowest level of all the species found in Nepal, and is, therefore, probably the tenderest of those from that part of the world. |