254 



SALICACEvE. 



[Diclinous Exogens, 



Order LXXX. SALICACEiE .— Wiiaowworts. 



, C. Richard in Ach, 

 Meitner, p. 348. 



Richard. EUm. de la 



Amentacese, Juss. Gen. 407. (1789) in part.— Salicineas, L 

 Bot.,ed. 4., 500 ; Endl. Gen. xcix. . 



Diagnosis.— Arnental Exogens, with a \-celled ovary, and numerous cottony seeds 



Trees or shrubs. Leaves alternate, simple, with deliquescent primary veins, and 



frequently with glands on the edge or stalks ; stipules deciduous or persistent, r lowers 



$ $ , naked or with a membranous cup- 

 like calyx, amentaceous. $ : Stamens 

 distinct or monadelphous ; anthers 2- 

 celled. ? : Ovary superior, 1 -celled ; 

 ovules numerous, erect, anatropal, at tho 

 base of the cell, or adhering to the lower 

 part of the sides ; style 1 or ; stigmas 

 2 or 4. Fruit leathery, 1-celled, 2-valved, 

 many-seeded. Seeds either adhering to 

 the lower part of the axis of each valve 

 or to the base of the cell, very small, 

 covered over with long silky hairs 

 springing from their base ; albumen ; 

 embryo erect ; radicle inferior. 



The downy seeds of Willows and 

 Poplars, growing at the base of leathery 

 2-valved capsules, give such plants a 

 mark of recognition which cannot be 

 mistaken. In this respect they are quite 

 different, not only from the remainder 

 of the Arnental Alliance, but from the 

 whole diclinous group. Their nearest 

 relation is apparently, on the one hand, 

 with Liquidam- 

 bars, which, like 

 them, have a 

 many-seeded dou- 

 ble fruit, and on 

 the other with the 

 Birchworts, with 

 which they agree 

 in their naked 

 male flowers and 

 double fruit. Ta- 

 marisks have been 



regarded as somewhat allied, because their fruit has a similar structure ; but the plants 

 are otherwise totally different. -n.~* 



Natives generally, of the same localities as Birchworts, but extending even further 

 to the north than those plants. The most northern woody plants that are known are the 

 Willows, Salix arctica and polaris. The Order is found sparingly in Barbary, and there 

 is a species of Willow even in Senegal. _ 



They are valuable trees, either for their timber or for economical purposes, tlie 

 Willow the Sallow, and the Poplar being the representatives of the Order. The bark is 

 usuallv'astringent, tonic, and stomachic ; that of Populus tremuloides is known as a 

 febrifuge in the United States ; of P. tremula and alba, in Europe. A crystalhsable prin- 

 ciple, Jailed Salicine,has been obtained from Salix helix, which, according to Majeiidie, 

 arrests the progress of a fever with the same power as sulphate of quinia. lhe best 

 species to prepare it from are said to be S. fragilis, pentandra, Russelhana, vitelhna, and 

 purpurea (the bitterest of all) in Europe, and criocephala, nigra, and conifera, in the 

 United States. Populine, a substance resembling Mannite, has been obtained from tlie 

 leaves and bark of some poplars. Poplar buds, especially those of P.nigra,balsannfera,and 



4 Fig. CLXX. 



FiE. CLXX. - Populus. 1. nigra $ ; 8. tremula ? : 3. a male flower ; 4. a female flower; 5. a 

 ripe capsule ; 6. a seed ; 7. the same more magnified, and split to show the embryo. 



