96 



pervades all the order, has caused them to be employed even as febrifuges, 

 tonics, and stomachics. Cork is the bark of Gtuercus suber ; it contains a pe- 

 culiar principle called Suberin (Turner, 700), and an acid called the Suberic 

 (Ibid. 641). The galls that writing ink is prepared from are the produce of 

 the Oak, from which they derive their astringency. The acorns of a species 

 known in the Levant under the name of Velonia (Gluercus eegilops) are im- 

 ported for the use of dyers. 



Examples. Gluercus, Corylus, Fagus. 



LXXXIII. BETULINE^. The Birch Tribe. 



Amentaceje, Juss. Gen. 407. (1789) in part; Lindl. Synops. § 228. (1829). — Betulinejb, L. 

 C. Richard MSS. A. Richard. Elem. de la Bot. ed. 4. 562. (1828.) 



Diagnosis. Achlamydeous dicotyledons, with a 2-celled ovarium, definite 

 pendulous seeds, and amentaceous flowers. 



Anomalies. The staminiferous flowers have occasionally a distinct calyx. 



Essential Character. — Mowers diclinous, monoecious, amentaceous; the stamniferoua 

 sometimes having' a membranous lobed calyx. Stamens distinct, scarcely ever monadcl- 

 phous ; anthers 2-celled. Ovarium superior, 2-celled ; ovules definite, pendulous ; style sin- 

 pie, or none; stigmas 2. Fruit membranous, indehiscent, by abortion 1- celled. Seeds pen- 

 dulous, naked ; albumen none; embryo straight ; radicle superior. — Trees or shrubs. Leaves 

 alternate, simple, with the vena primarire running straight from the midrib to the margin; 

 stipula deciduous. 



Affinities. This order approaches more near to Urticeae and Cupuliferae 

 than either Plataneae or Salicinese, which may be considered dismemberments 

 of it. In the male flowers of several species there is a distinct membranous 

 calyx, very like that of Ulmus ; the seeds are definite and pendulous, and the 

 leaves have the same venation as Cupuliferae. It is distinguished by the 2 dis- 

 tinct cells of the fruit, by the want of a calyx to the female flowers, and by its 

 solitary pendulous seeds. 



Geography. Inhabitants of the woods of Europe, Northern Asia, and 

 North America, and even making their appearance on the mountains of Peru 

 and Colombia. 



Properties. Fine timber-trees, usually with deciduous leaves ; their bark 

 astringent, and sometimes emploj^ed as a febrifuge ; but chiefly valued for their 

 importance as ornaments of a landscape. Their wood is often light, and of 

 inferior quality, but that of the Black Birch of North America is one of the 

 hardest and most valuable we know. 



Examples. Betula, Alnus. 



LXXXIV. SALICINE.E. The Willow Tribe. 



Amentaceje, Jvss. Gen. 407. (1789) in part; Lindl. Synops. § 229. (1829).— Salicinejb, L. C 

 Richard MSS. ; Ach. Richard. Elem. de la Bot. ed. 4. 560. (1828.) 



Diagnosis. Achlamydeous dicotyledons, with a 1- or 2-celled ovarium, 

 indefinite comose seeds, and amentaceous flowers. 

 Anomalies. 



