794 TREES OF NORTH AMERICA 



isolated stations; more abundant on the mountains of western Pennsylvania, becoming 

 exceedingly common farther south and occupying the steep banks of streams up to al- 

 titudes of 3000; of its largest size on the high mountains of eastern Tennessee and the 

 Carolinas, and here often forming thickets hundreds of acres in extent. 



Often cultivated as an ornament of parks and gardens in the United States, and in 

 Europe, and one of the parents of a number of distinct and beautiful hybrids. 



3. KALMIA L. 



Trees or shrubs, with scaly bark, terete branchlets without a terminal bud, minute axil- 

 lary leaf-buds, elongated axillary inflorescence-buds covered by imbricated scales, and 

 fibrous roots. Leaves ovate-oblong or linear, short-petiolate, with flat entire margins, 

 coriaceous, persistent or deciduous in one species. Flowers on slender pedicels bibracteo- 

 late at the base, from the axils of foliaceous coriaceous ovate or acute persistent bracts, 

 in axillary umbels; calyx 5, rarely 6-parted, the divisions imbricated in the bud, persistent 

 under the fruit; corolla 5, rarely 6-lobed, rose-colored, purple, or white, saucer-shaped, 

 with a short tube and 10 pouches just below T the 5 or 6-parted limb, the lobes ovate, 

 acute, before anthesis prominently 10 or 12-ribbed from the pouches to the acute apex of 

 the bud, the salient keel of the ribs running to the point of the lobes and to the sinuses; 

 stamens 10, shorter than the corolla; filaments filiform; anthers oblong, each cell opening 

 by a short apical oblong longitudinal pore, at first free in the bud, the filaments then erect, 

 later received in the pouches of the corolla, the filaments becoming bent back by its 

 enlargement and expansion, straightening elastically and incurving on the release of the 

 anthers, and in straightening discharging the pollen-grains; disk prominently 10-lobed, 

 ovary subglobose, 5-celled; style filiform, exserted, crowned W 7 ith a capitate stigma; ovules 

 numerous in each cell, inserted on a 2-lipped placenta, pendulous or spreading from near 

 the top of the thin columella, few-ranked, anatropous. Fruit a woody many-seeded glo- 

 bose slightly 5-lobed 5-celled capsule, tardily septicidally 5-valved, the valves crustaceous. 

 ultimately opening down the middle by a narrow slit and separating from the persistent 

 placenta-bearing axis. Seeds oblong or subglobose, minute; seed-coat crustaceous or 

 membranaceous; embryo in fleshy albumen, terete, near the hilum; radicle erect, rather 

 shorter than the oblong cotyledons. 



Kalmia with six species is North American and Cuban, one species occasionally becom- 

 ing under favorable conditions a small tree. 



The generic name is in honor of the Swedish traveler and botanist, Peter Kalm (1715- 

 1779). 



1. Kalmia latifolia L. Laurel. Mountain Laurel. 



Leaves sometimes in pairs or in 3's, conduplicate in the bud, each leaf in the bud in- 

 closed by the one immediately below it, oblong or elliptic-lanceolate, acute or rounded and 

 tipped at apex with a callous point, and gradually narrowed at base, rarely oval to oblong- 

 obovate and rounded at ends (f . obtusata Rehd.), when they unfold slightly tinged with pink 

 and covered with glandular white hairs, and at maturity thick and rigid, dark rather dull 

 green above, light yellow-green below, 3'-4' long and l'-l|' wide, with a broad yellow mid- 

 rib and obscure immersed veins; beginning to fall during their second summer; petioles stout, 

 terete or slightly flattened, about f ' in length. Flowers opening from early in April in 

 southern Mississippi to the 20th of June at the north ; inflorescence-buds appearing in the 

 autumn from the axils of upper leaves, beginning to lengthen with the first warm days of 

 spring and usually developing 2 or several lateral branches, the whole forming a compound 

 many-flowered corymb of numerous crowded fascicles more or less covered with dark 

 scurfy scales, 4 '-5' in diameter, and overtopped at the flowering time by the Jeafy branches 

 of the year; flowers nearly 1' in diameter, on long slender red or green pedicels covered 

 with glandular hairs, and furnished at base with 2 minute acute bractlets, developed 

 from the axils of acute persistent bracts sometimes %' long; calyx divided nearly to the 

 base into narrow acute thin green lobes; corolla white (f. alba Rehd.), rose-color, or deep 



