458 BETULACE^E. (BIRCH FAMILY.) 



2. COMPTONIA, Solander. Sweet-Fern. 



Flowers frequently monoecious ; the sterile in cylindrical catkins, with kidney, 

 ueart-shaped pointed scale-like bracts, and 3-6 stamens ; the fertile in globular 

 catkins, bur-like : ovary surrounded by 8 long linear-awl-shaped scales, persistent 

 around the ovoid-oblong smooth nut : otherwise as in Myrica. — Leaves linear- 

 lanceolate, pinnatifid with many rounded lobes, thin, appearing rather later than 

 the flowers. Stipules half heart-shaped. (Named after Henry Compton, Bishop 

 of London a century ago, a cultivator and patron of botany.) 



1. C. aspleilifolia, Ait. (Myrica Comptonia, C. DC.) — Sterile hills, 

 New England to Virginia, Wisconsin, and northward. April, May. — Shrub 

 l°-2° high, with sweet-scented fern-like leaves. 



Order 104. BETUlACEJE. (Birch Family.) 



Monoecious trees or shrubs, with alternate simple mostly straight-veined 

 leaves, both kinds of flowers in scaly catkins, 2 or 3 under each bract, and 

 no involucre to the naked \ -celled and 1-seeded often winged small nut, 

 which results from a 2-celled and 2-ovuled ovary. Stipules often early 

 deciduous. Stigmas 2, thread-like. Seed anatropous, suspended: no 

 albumen. Cotyledons flattish, oblong, foliaceous in germination. — Com- 

 prises the two genera, Birch and Alder. 



1. BE TULA, Tourn. Birch. 



Sterile flowers 3, and bractlets 2, under each shield-shaped scale or bract of 

 the catkins, consisting each of a calyx of one scale bearing 4 short filaments 

 with 1 -celled anthers, or strictly of 2 two-parted filaments, each division bear- 

 ing an anther-cell. Fertile flowers 2 or 3 under each 3-lobed bract, without 

 bractlets or calyx, each of a naked ovary, becoming a broadly winged and scale- 

 like nutlet or small samara crowned with the two spreading stigmas. — Outer 

 bark usually separable in sheets, that of the branchlets dotted. Twigs and 

 leaves often spicy-aromatic. Foliage mostly thin and light. Buds sessile, 

 scaly. Sterile catkins long and drooping, terminal and lateral, formed in sum- 

 mer, remaining naked through the succeeding winter, and expanding their 

 golden flowers in early spring, with or preceding the leaves : fertile catkins ob- 

 long or cylindrical, usually terminating very short 2-leaved early lateral branches 

 of the season. (The ancient Latin name.) 



* Trees, with brown or yellow-gray bark on the trunk, sweet-aromatic as well as the 

 twigs, membranaceous and straight-veined Hornbeam-like leaves with a heart- 

 shaped or rounded base, on short petioles, and sessile very thick fruiting catkins : 

 their about equally S-cleft scales rather persistent : wing of fruit on each side not 

 broader than the seed-bearing body. 



1. B. lenta, L. (Cherry-B. Sweet or Black Birch.) Bark of trunk 

 dark brown, close (outer layers scarcely laminate), very sweet-aromatic; leaves 

 ovate or oblong-ovate from a more or less heart-shaped base, acuminate, sharply 



