BETULACE^E. 



Nat. syst. ed. 2. p. 171. 



BETULA. 



$ . Catkins cylindrical, lax, imbricated all round, with ter- 

 nate, concave scales ; the middle one largest, ovate. Filaments 

 10-12, shorter than the middle scale, to which they are at- 

 tached. 2 . Catkins similar, but more dense ; scales horizontal, 

 peltate, dilated outwards, 3-lobed, 3-flowered. Ovary com- 

 pressed, bordered, of 2 cells. Styles 2, awl-shaped, downy. 

 Stigma simple. Nut oblong, deciduous, winged on each side, of 



1 cell, with a solitary seed. 



604. B. alba Linn, sp.pl. 1393. Eng. Bot. t. 2198. Smith 

 Eng. Fl. iv. 153. — Woods and rocks in moist mountainous parts 

 of Europe. (Birch.) 



A tall tree, with the epidermis of the trunk whitish and peeling off 

 readily in thin slips. Branches long, slender, nearly erect, covered 

 when young with a short close down. Leaves ovate or slightly deltoid, 

 acuminate, unequally serrated, slightly downy on the underside. 

 Catkins terminal, stalked, pendulous. — Independently of many useful 

 purposes to which the bark of this plant is (applicable, it has also been 

 employed as a febrifuge, and yields by distillation a pyrogenous oil of 

 a very peculiar kind to which Russia leather, dressed with it, is said to 

 owe its remarkable odour. 



ALNUS. 



$ . Catkin lax, imbricated all round with ternate scales, the 



2 lateral of which are minute, the central 3-flowered. Calyx 

 tubular, 4-lobed. Filaments 4, opposite the lobes of the calyx. 



? . Catkin firm, ovate, composed of 2-flowered simple scales. 

 Calyx 0. Ovary 2-celled, with 2 parallel, tapering, deciduous 

 styles. Nut ovate, bony, angular, not winged, 2-celled, 2-seeded. 



605. A. glutinosa Gcertn. ii. 54. Smith Eng. Fl. iv. 132 



Betula Alnus Linn. sp. pi. 1 394. $ E. Bot. t. 1508. — Meadows 

 and wet places all over Europe. (Alder.) 



A small crooked tree, with spreading, round smooth, dark brown 

 branches, glutinous when young. Leaves roundish-wedge-shaped, ob- 

 tuse, plaited, serrated, glutinous, deep green, with numerous parallel 

 veins, having bundles of hairs in their axils ; stipules roundish, entire. 

 — A decoction of the bark is employed as a gargle in relaxation of the 

 mucous membranes of the fauces ; and in double the dose of cinchona 

 it has been administered with success in cases of ague. 

 293 u 3 



