ERICACEAE 799 



6. ARBUTUS L. 



Trees or shrubs, with astringent bark exfoliating from young stems in large thin scales, 

 smooth terete red branches, and thick hard roots. Leaves petiolate, entire or dentate, 

 obscurely penniveined, persistent. Flowers on clavate pedicels bibracteolate at base from 

 the axils of ovate bracts, in simple terminal compound racemes or panicles, with scarious 

 scaly persistent bracts and bractlets; calyx free from the ovary, 5-parted nearly to the base, 

 the divisions imbricated in the bud, ovate, acute, scarious, persistent; corolla ovoid-urceo- 

 late, white, 5-toothed, the teeth obtuse and recurved; stamens 10, shorter than the corolla; 

 filaments subulate, dilated and pilose at base, free, inserted in the bottom of the corolla; 

 anthers short, compressed laterally, dorsally 2-awned, the cells opening at the top inter- 

 nally by a terminal pore; ovary glandular-roughened, glabrous or tomentose, sessile or 

 slightly immersed in the glandular 10-lobed disk, 5 or rarely 4-celled; style columnar, sim- 

 ple, exserted; stigma obscurely 5-lobed; ovules attached to a central placenta developed 

 from the inner angle of each cell, amphitropous. Fruit drupaceous, globose, smooth or 

 glandular-coated, 5-celled, many-seeded; flesh dry and mealy; stone cartilaginous, often 

 incompletely developed. Seeds small, compressed or angled, narrowed and often apiculate 

 at apex; seed-coat coriaceous, dark red-brown, slightly pilose; embryo axile in copious 

 horny albumen, clavate; radicle terete, erect, turned toward the hilum. 



Arbutus with ten or twelve species inhabits southern and western North America, Central 

 America, western, southern and eastern Europe, Asia Minor, northern Africa, and the 

 Canary Islands. Three species occur within the territory of the United States. Arbutus 

 produces hard close-grained valuable wood often made into charcoal, used in the manu- 

 facture of gunpowder. The fruit possesses narcotic properties, and the bark and leaves 

 are astringent. 



Arbutus is the classical name of the species of southern Europe. 



CONSPECTUS OF THE SPECIES OF THE UNITED STATES. 



Bark of old trunks dark red-brown. 



Ovary glabrous; leaves oval or oblong. 1. A. Menziesii (B, G). 



Ovary pubescent; leaves oval, ovate, or lanceolate. 2. A. texana (C). 



Bark of old trunks ashy gray; ovary glabrous, conspicuously porulose; leaves lanceolate or 



rarely narrow-oblong. 3. A. arizonica (H). 



1. Arbutus Menziesii Pursh. Madrona. 



Leaves oval or oblong, rounded or contracted into a short point at apex, and rounded, 

 subcordate or cuneate at base, with slightly thickened revolute entire or occasionally on 

 young plants sharply serrate margins, when they unfold light green or often pink, especially 

 on the lower surface, and glabrous or slightly puberulous, and at maturity thick and coria- 

 ceous, dark green and lustrous above, pale or often nearly white below, 3 '-5' long and 1|'- 

 3' wide, with a thick pale* midrib and conspicuously reticulated veinlets; persistent until 

 the early summer of their second year and then turning, orange and scarlet and falling 

 gradually and irregularly; petioles stout, grooved, $'-!' in length, often slightly wing- 

 margined toward the apex; often producing late in summer a second crop of smaller leaves. 

 Flowers about -J-' long, with a glabrous ovary, appearing from March to May on short slen- 

 der puberulous pedicels from the axils of acute scarious bracts ciliate on the margins, in 

 spicate pubescent racemes forming a cluster 5'-6' long and broad. Fruit ripening in the 

 autumn, subglobose or occasionally obovoid or oval, |' long, bright orange-red, with thin 

 glandular flesh and a 5-celled more or less perfectly developed thin-walled cartilaginous 

 stone; seeds several in each cell, tightly pressed together and angled, dark brown and pilose. 



A tree, 80-125 high, with a tall straight trunk 4-5 in diameter, stout upright or 

 spreading branches forming a narrow oblong or broad round-topped head, and slender 

 branchlets light red, pea-green, or orange-colored and glabrous when they first appear, or 

 on vigorous young plants sometimes covered with pale scattered deciduous hairs, becoming 



