POPULAR FLORA. 199 



-I- H- Leaves or some of them a little lobed, broader upwards. 



10. "Water Oak. Leaves smooth and shining, spatulate or wedge-obovate, with a tapering base; 

 cup very short ; acorn globular. Swamps, S. Q. aqvudca. 



11. Black-Jacic Oak. Leaves thick and large, broadly wedge-shaped, and with 3 or 5 obscure 

 lobes at the summit, shining above, rusty-downy beneath, the lobes or teeth bristle-pointed. 

 Small tree, in barrens. Q. nigra. 



^ H_ M_ Leaves pinnatifid or lobed, long-stalked, the lobes or teeth bristle-pointed. 



12. Bear or Scrub Oak. Leaves wedge-obovate, slightly about 5-lobed, whitish-downy beneath. 

 A crooked shrub, 3'' to 8° high; in barrens and rocky woods. Q. U'uifuUa. 



13. Spanish Oak. Leaves grayish-downy beneath, narrow above, and with 3 to 5 irregular and nar- 

 row often curved lobes; acorn very short. Dry soil, S. & E. A fine tree. Q.falcata. 



14. Quercitron Oak. Leaves rusty-downy when young, becoming nearly smooth when old, oblong- 

 obovate, sinuate-pinnatifid; cup top-shaped, coarse-scaly; acorn globular or depressed. Large 

 tree; the inner bark thick and yellow, used for dyeing. Q. tinctbria. 



15. Scarlet Oak. Very like the last, but the oval or oblong leaves smooth and shining, deeply pin- 

 natifid (turning deep scarlet in autumn), the lobes cut-toothed ; acoi'n rather longer than wide. 

 Large tree, common in rich woods. Q. coccinea. 



16. Red Oak. Leaves smooth, pale beneath, oblong or rather obovate, with 4 to 6 short lobes on 

 each side; acorn oblong-oval, 1' long, with a short saucer-shajDed cup of fine scales. Common 

 tree in rocky woods, &c. Q. rubra. 



17. Pin or Swamp Spanish Oak. Leaves smooth and bright green on both sides, deeply pin- 

 natifid, oblong; the lobes diverging, cut and toothed, acute; acorn globular, only i' long. Low 

 grounds, N. Q. paliislris. 



86. BIRCH FAMILY. Order BETULACE^. 



ISIonoecious trees, witli siiDple serrate leaves, and both kinds of flowers in scaly catkins 

 (Fig. 146), two or three blossoms under each scale. Sterile flowers each with 4 stamens 

 and a small calyx : fertile flowers with a 2 celled ovary bearing 2 long stigmas, and in fruit 

 becoming a scale-like akene or small key. Only two genera : — 



Sterile flowers with a calyx of one scale: fertile flowers 3 under each 3-lobed bi'act; each 

 consisting of a naked ovary, in fruit becoming a broad- winged little key. Bark and 

 twigs aromatic, {Bctula) BiRCir. 



Sterile flowers generally with a 4-parted calyx: fertile catkins short and thick, with hard 



scales, not falling off: fruit generally wingless, {Alnus) Alder. 



Birch. Betula. 



1. White Birch. A small and slender tree, with white outer bark; leaves ti-iangular, very taper- 



pointed, on long and slender stalks. Common E. B. alba. 



2. Paper B. A large tree, with white outer bark, peeling ofi" in papery layers, and ovate or heart- 



shaped leaves. Common N. B. ixiiyyviicea. 



3. River B. Tree, with ovate and angled acutish leaves, on short stalks, a brownish close bark, 



and short woolly fertile catkins. Common S. & W. B. nigra. 



