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Essential Character. — F'loircrs diclinous, either monoecious or dioecious, amentaceous. 

 Slamens distinct or monadelplious; anthers 2-cellcd. Ovarium superior, 1- or 2-celled ; 

 ovules numerous, erect, at the base of the cell, or adhering - to the lower part of the sides ; style 

 1 or ; stigmas 2. Fruit coriaceous, 1- or 2-celled, 2-valvcd, many-seeded. Seeds either ad- 

 hering' to the lower part of the axis of each valve, or to the base of the cell, comose ; albumen 

 0; embryo erect ; radicle inferior. — Trees or shrubs. Leaves alternate, simple, with deliques- 

 cent venae primarire, and frequently with glands ; stipula deciduous or persistent. 



Affinities. The hairy seeds, and polyspermous 2-valved fruit, distinguish 

 this from Betulineae, the only order with which it is likely to be confounded. 

 It is usually combined with that order and Cupulifera?, under the name of 

 Amentaceee ; but it is more consonant with modern views of division to keep 

 them all separate. 



Geography. Natives, generally, of the same localities as Bctulinese, but 

 extending further to the north than the species of that order. The most 

 northern woody plant that is known is a kind of Willow, Salix arctica. They 

 are found sparingly in Barbary, and there is a species of Willow even in Se- 

 negal. 



Properties. Valuable trees, either for their timber or for economical pur- 

 poses ; the Willow, the Sallow, and the Poplar, being the representatives. 

 Their bark is usually astringent, tonic, and stomachic ; that of Populus tre- 

 muloides is known as a febrifuge in the United States ; the leaves of Salix 

 herbacea, soaked in water, are employed in Iceland for tanning leather. Wil- 

 low bark has been found by Sir H. Davj' to contain as much tanning principle 

 as that of the Oak. Ed. P. J. 1. 320. It has lately acquired a great reputation 

 in France as a febrifuge. [Its active principle is a vegeto-alkali, analogous to 

 Q.uinia, and called Salicine by its discoverer, M ] 



Examples. Populus, Salix. 



LXXXV. PLATANE.E. The Plane Tribe. 



Plataxeje, Lestiboudois according to Von Marlius. Hort. Reg. Monaccnsis, p. 46. (1829.) 



Diagnosis. Achlanvydeous dicotyledons, with a 1-celled ovarium, pendu- 

 lous ovules, alternate leaves, amentaceous flowers. 

 Anomalies. 



Essential Character. — Flowers amentaceous, naked; the stamens and pistils in distinct 

 amenta. Stamens single, without any floral envelope, but with several small scales and ap- 



Eendages mixed among them; anthers linear, 2-celled. Ovaria terminated by a thick style, 

 aving the stigmatic surface on one side ; ovules solitary, or two, one above the other, and 

 suspended. Nuts, in consequence of mutual compression, clavate, with a persistent recurved 

 style. Seeds solitary, or rarely in pairs, pendulous, elongated ; testa thick ; embryo long, taper, 

 lying in the axis of fleshy albumen, with the radicle turned to the extremity next (opposite A. 

 Rich.) the hilum. — Trees or shrubs. Leaves alternate, palmate, or toothed, with scarious 

 sheathing stipula:. Amenta round, pendulous. 



Affinities. Formerly comprehended in the tribe called Amentaceae, this 

 order is particularly known by its round heads of flowers, its 1 -celled ovarium, 

 containing 1 or 2 pendulous ovula, and its embryo lying in fleshy albumen, by 

 which it is distinguishable from both Betulineae, Myriceae, and Artocarpea?, 

 with all which, especially the latter, it has a close affinity. From the latter, 

 indeed, it is chiefly known by the want of calyx, by the presence of albumen, 

 and the absence of milk ; the habit of the two orders being much the same. 

 According to Gaertner, the radicle is next the hilum ; according to Achille 

 Richard, (Diet. Class. 14. 23.,) it is at the other extremity. 



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