* 
CXXVL MYRICACEA. 499 
Shrub 2—3f high, mountains, N. Y. and Penn. Pursh. ‘In.several low places 
towards the hills” Penn. Bartram. Cedar non eae re Ohio, Sullivant 
(fide Tuckerman.) .A very obscure species, unless it be the following. 
7. B. guanpuLosa. Michx. Glandular Dwarf Birch. 
Low ; branches glandular-punctate, glabrous ; lvs. obovate, entire at base, 
obtusely ‘serrate, glabrous ;. pers aments oblong’; scales half 3-cleft, lobes ovate- 
oblong, middle one rather longest; mut orbicular, with a narrow margin—A 
beautiful shrub, inhabiting the mountainous districts of the N. and N. W. 
States'!! N. ‘to Hudson’s Bay. Height 2—4f. Leaves about 9” by 6.or 7”, very 
regularly teothed.—If this shrub be distinctfrom the preceding, it may be known 
by its glandular-dotted branches and its want of pubescence—scarcely by its 
variable leaves. : 
8. B. Lirrecuiana. Tuckerman. 
Low, glabrous; branches resinous-punctate; dvs. suborbicular, coarsely 
serrate ; fertile aments oblong-cylindric, scales trifid, lobes oblong-obovate, mid- 
dle one lo —White Mts., Tuckerman. Shrub.somewhat erect. Leaves 2 
—4 mes eee 1 those of B. nana. 
9. B. wana. Tiny Birch. 
‘Low, smooth; dvs. orbicular, crenate, reticulated ‘beneath ; ‘scales of ‘the 
ament deeply 3-parted ; seeds orbicular, nearly wingless.—This miniature tree 
is found on the summits:of Mt. Clinton, Mt. Franklin, &c., of the White Mts.! 
It is scarcely more 'than’a foot in height, often but a few inches, the branches 
few and ‘straggling, the leaves 3—$’ in diameter, smooth both sides, pale and 
distinctly reticulate beneath, and on petioles 1—2” long. 
2, ALNUS. Tourn. 
& Ament long, cylindric, composed of cuneate, truncate, 3-lobed, 
3-flowered bracts; cal. 4-parted; sta. 4. 9 Ament ovoid; bracts 2- 
flowered ; 3-fid; cal. 0; nut wingless, compressed.— Shrubs, arising 
from large. and strong roots. Buds pedunculate. Lvs. plicate in ver- 
nation, alternate, simple, deciduous. = 
‘1. A. cina. Willd. (A. glauca. Michr. Betula incana. 
Lvs, submembranaceous, oblong, acutish, obtuse at bz 
gin somewhat lobed, sharply serrate, glaucous-pubescent benez 
their axils naked; stip. oblong-lanceolate; fertile aments oval.—1 
in N. Eng. and Mid. States. A tall shrub or small tree, readily disti 
by the form and pubescence of the leaves. 
», A. RuBRa. Marsh. (A serrulata. Wilid.and tst edit.) Common Alder. 
0s. obovate, acuminate, doubly serrulate, the veins.and their axils haify 
beneath; stip. elliptical, obtuse——A well known shrub. growing in clumps, and 
forming thickets on the borders of ponds and rivers,‘and ‘in swamps. Stems 
— aa, straight, 10—15f in-height. Leaves 2—4’ long and 4 as wide, 
strongly veined; petioles 4—}/ long. Aments 2—3’ long, slender, pendulous, 
fascicled atthe ends of the branches,; fertile ‘ones short, thick, dark brown, per- 
sistent, séveral together a little below the sterile ones. March, April. 
3. A. crispa. Michx. (Betula‘crispa. Ait.) 
Iws. oval, acute, obtusish at base, doubly serrate, clothed with a soft vis- 
cid pubescence, or subglabrous, villous on ‘the veins and axils beneath; stip. 
broadly ovate; fertile aments on long peduncles, oval.—W hite Mts., Tuckerman, 
Green Mts., Robbins, Can., Michaux. An elegant shrub,3—4f high. Leaves 
varying to bread-ovate, rarely cordate, nearly smooth in the alpine state, other- 
wise softly pubescent and sprinkled with resinous particles. Apr. 
Oxven CXXVI. MYRICACE A.—Gateworrs. 
Shrubs or small trees, aromatic, covered with resinous glands or dots. Lvs. alternate, simple. 
Fis. monecious or diecious, amentaceous, each axillary to'a bract. 
Sterile.—Sta. 2-6. Anth. 2—4-celled, opening longitudinally. 
Fertile.—Ova. 1-celled, 1-ovuled, surrounded by several hypogynous' scales, 
