BETULACEA. 
SILVA OF NORTH AMERICA. 
69 
and Alnus rugosa,’ are shrubs. During the tertiary period species of Alnus were probably much 
more numerous, especially in Europe, where palzontologists have described about thirty from the 
eocene and miocene formations.? 
Alnus produces soft straight-grained wood, very durable in water, and astringent bark and strobiles, 
which are used in tanning leather* and in medicine.t The most valuable species are Alnus glutinosa” 
tier, Enum. Pl. Jap. i. 458. — Boissier, Fl. Orient. iv. 1180. — Sar- 
gent, Forest Trees N. Am. 10th Census U. S. ix. 164. — Watson & 
Coulter, Gray’s Man. ed. 6, 473. —Hempel & Wilhelm, Béume 
und Strducher, ii. 15, £. 124, 125, +. 13. 
Betula Alnus, 6 incana, Linneus, Spec. 983 (1753). — Du Roi, 
Harbk. Baumz. i. 109. 
Betula incana, Linnzus f. Suppl. 417 (1781).— Roth, Tent. Fi. 
German. ii. 477. — Willdenow, Berl. Baumz. 45. 
Betula-Alnus glauca, Marshall, Arbust. Am. 20 (1785). 
Alnus lanuginosa, Gilibert, Exercit. Phyt. ii. 402 (1792). 
Alnus glauca, Michaux f. Hist. Arb. Am. iii. 322, t. 4, f. 2 
(1813). — Bigelow, Fi. Boston. ed. 3, 367. 
Alnus incana, var. glauca, Gray, Man. 423 (1848). 
In North America, where it is the common Alder of swamps 
and river-banks in the northeastern parts of the continent, forming 
dense shrubby thickets rarely more than ten or twelve feet high, 
Alnus incana is distributed from Newfoundland to the eastern 
base of the Rocky Mountains, ranging southward in the United 
States to Staten Island, New York, Wisconsin, and eastern Ne- 
braska. 
In many forms it is spread all over northern and central Europe 
from northern Scandinavia and Russia to France, northern Italy, 
and the Caucasus, growing in the extreme north on sandy plains 
near streams, but in the south usually on mountain slopes, and some- 
times attaining a height of seventy feet ; it is the common Alder 
of Siberia and northeastern Asia, and is very abundant in northern 
Japan, becoming, on the island of Yezo, a stately tree fifty or 
sixty feet in height, with a trunk often two or three feet in diame- 
ter. Here it flourishes in moist rich soil on low slopes rising from 
streams bordered with the largest of the Japanese Alders, Alnus 
Japonica, Siebold & Zuccarini, which is a pyramidal tree eighty or 
ninety feet tall, and clothed to the ground with large dark green 
lustrous leaves (Sargent, Forest Fl. Japan, 63). In Japan the wood 
of Alnus incana is used in turnery, and is manufactured into boxes 
and other small articles. 
1 K. Koch, Dendr. ii. pt. i. 635 (1872). 
Betula Alnus (rugosa), Du Roi, 1. c. 112 (1771). 
Betula-Alnus rubra, Marshall, J. c. 20 (1785). 
Betula serrulata, Aiton, Hort. Kew. iii. 338 (1789). — Willde- 
now, J. c.— Abbot & Smith, Insects of Georgia, ii. 183, t. 92. — 
Michaux, FV. Bor.-Am. ii. 181. 
Alnus serrulata, Willdenow, Spec. iv. pt. i. 336 (1805) ; Enum. 
965 ; Berl. Baumz. ed. 2, 21. — Nouveau Duhamel, ii. 216. — Per- 
soon, Syn. ii. 550.— Desfontaines, Hist. Arb. ii. 488.— Aiton, 
Hort. Kew. ed. 2, v. 259. — Michaux f. Hist. Arb. Am. iii. 320, t. 
4, f. 1. — Pursh, Fl. Am. Sept. ii. 623. — Nuttall, Gen. ii. 206. — 
Elliott, Sk, ii. 567. — Torrey, Fl. N. Y. ii. 202, t. 115. — Spach, 
Ann. Sci. Nat. sér. 2, xv. 205 (Revisio Betulacearum). — Emerson, 
Trees Mass. 218 ; ed. 2, i. 248, t. — Chapman, FV. 429. — Regel, 
Bull. Soc. Nat. Mosc. xxxviii. pt. ii. 432 (Gattungen Betula und 
Alnus) (exel. oblongifolia) ; De Candolle Prodr. xvi. pt. ii. 188 
(excel. y oblongifolia). — Curtis, Rep. Geolog. Surv. N. Car. 1860, 
iii. 108. — Sargent, Forest Trees N. Am. 10th Census U.S. ix. 
164. — Watson & Coulter, J. c. 
Alnus incana, B, Hooker, Fl. Bor.-Am. iii. 157 (1839). 
Alnus rubra, Tuckerman, Am. Jour. Sci. xlv. 32 (not Bongard) 
(1843). 
Alnus glutinosa, 8 serrulata, Regel, Nouv. Mém. Soc. Nat. Mosc. 
xiii. 164, t. 11, £. 6-10 (Monographia Betulacearum) (1861). 
Alnus glutinosa, var. rugosa, Regel, /. c. 165, t. 11, f. 8-10 
(1861). 
Alnus rugosa is distributed from Essex County, Massachusetts, 
westward to southeastern Minnesota and southward to northern 
Florida and the valley of the Trinity River in Texas. Less com- 
mon in the north than in the southeastern states, where it is very 
abundant and the only species of Alder, Alnus rugosa sometimes 
grows to the height of twenty-five or thirty feet, sending up from 
the ground numerous slender stems, and forming a broad round- 
topped shrub with cuneate-obovate leaves rounded or acute at the 
apex, green on both surfaces, and smooth or puberulous on the 
lower, and ovate strobiles. 
2 Lesquereux, Rep. U. S. Geolog. Surv. vii. 139 (Contrib. Fossil 
Fl. W. Territories, iii.). — Saporta, Origine Paléontologique des 
Arbres, 142. — Zittel, Handb. Paleontolog. ii. 411. 
8 Neubrand, Die Gerbrinde, 220. — Dreykorn & Reichardt, Ding- 
ler Polytech. Jour. exev. 157 (Ueber den farbigen Gerbstoff des 
Erlenholzes); Archiv. der Pharm. ser. 2, exlii. 215. — Eitner, Erlen- 
rinde als Gerbmaterial, Der Gerber, iv. 84.— Hohnel, Die Gerbe- 
rinden, 56. 
4 Alder bark is an alterative and astringent, and in the United 
States is sometimes used in decoctions, in domestic practice, to 
purify the blood, in diarrhea, hematuria, and intermittent fevers, 
and as a gargle (Johnson, Man. Med. Bot. N. Am. 253.— U.S. 
Dispens. ed. 16, 1705). 
5 Gaertner, Fruct. ii. 54, t. 90 (1791). — Willdenow, Spec. l. c. 
334. — Brotero, Fl. Lusitan. i. 210.— De Candolle, Lamarck Fi. 
Fran. ed. 3, iii. 303. — Hornemann, Fl. Dan. xiii. t. 2302. — Guim- 
pel, Willdenow & Hayne, Adbbild. Holz. ii. 180, t. 135. — Hayne, 
Arzn. xiii. 48, t. 48. — Ledebour, Fi. Ross. iii. 657. — Reichenbach, 
Icon. Fl. German. xii. 4, t. 631. — Hartig, Forst. Culturpfl. Deutschl. 
338, t. 23. — Regel, Nouv. Mém. Soc. Nat. Mosc. l. c. 159; Bull. 
Soc. Nat. Mose. l. c. 430 ; De Candolle Prodr. I. c. 186. — Parlatore, 
Fl. Ital. iv. 124. — Boissier, 7. c. 1180. — Hempel & Wilhelm, 1. c. 
11, f. 121-123, t. 12. 
Betula Alnus, B glutinosa, Linnzus, Spec. 983 (1753). — Sco- 
poli, FZ. Carn. ed. 2, ii. 233. 
Betula glutinosa, Lamarck, Dict. i. 454 (1783). 
Alnus nigra, Gilibert, J. c. 401 (1792). 
Alnus communis, Nouveau Duhamel, ii. 212, t. 64 (1802). 
Alnus glutinosa (vulgaris), Persoon, J. c. (1807). 
Alnus rotundifolia, Stokes, Bot. Mat. Med. iv. 369 (1812). 
Alnus elliptica, Requien, Ann. Sci. Nat. sér. 1, v. 381 (1825). 
Alnus barbata, C. A. Meyer, Verz. Pl. Caucas. 43 (form with 
leaves hairy below along the principal veins) (1831). 
Alnus denticulata, C. A. Meyer, J. c. (form with leaves conspic- 
uously denticulate) (1831). 
Alnus Morisiana, Bertoloni, Fl. Ital. x. 163 (1854). 
Alnus Februaria, Otto Kuntze, Taschenfl. Leipz. 283 (1867). 
Alnus glutinosa is spread all over Europe, where it flourishes on 
the borders of streams and swamps in situations too wet even for 
