THE HEATH FAMILY 



ERICACE^ de CandoUe 



HIS family consists of about 55 genera, comprising some 1050 species 

 of trees or shrubs of wide geographic distribution, from arctic to 

 tropic regions; they are of no especial economic value except in medi- 

 cine. The leaves of the Bearberry, Arctostaphylos Uva-ursi Linnaeus, 

 a small trailing shrub, are largely used in medicine; Wintergreen, GauUheria 

 procumbens Linnaeus, was formerly important on account of its volatile oil, from 

 which salicylic acid, a valuable remedy for rheumatism, and a useful antiseptic, 

 was obtained ; this, however, is now secured more cheaply from other sources, and 

 the oil, which is also a favorite flavoring agent, is being replaced by a very similar 

 product obtained from the twigs and bark of the Cherry birch, Betula lenta 

 Linnaeus. Many members of this family are highly ornamental and some are well 

 known in cultivation, particularly the Azaleas, Rhododendrons, and Kalmias; in 

 Europe various species of Erica are also much grown. 



The Ericaceae have alternate, or rarely opposite or whorled, simple, usually 

 leathery and persistent leaves, without stipules. The flowers are variously clus- 

 tered, perfect or mostly so; the calyx consists of 4 to 7 distinct or partly united 

 sepals; the corolla is regular, or slightly 2-lipped, gamopetalous, but the usually 

 5 lobes sometimes nearly separate, the stamens equal in number or twice the num- 

 ber of the corolla-divisions, their filaments usually distinct; the anthers are 2-celled, 

 the sacs sometimes prolonged upward; the ovary is composed of 2 to 5 united car- 

 pek; styles united; stigma capitate or peltate; ovules usually numerous. The fruit 

 is a woody capsule, dryish drupe or berry-like; seeds numerous, or sometimes soli- 

 tary in each cell; endosperm fleshy; embryo central; cotyledons short. 



Petals separate. i. EUioUia. 



Petals united into a gamopetalous corolla. 

 Fruit a dry, dehiscent, woody capsule. 

 Capsules opening septicidally. 



Corolla without pouches for the anthers; capsule elongated, not de- 

 pressed. 2. Rhododendron. 

 Corolla with pouches for the anthers; capsule spherical or depressed. 3. Kalmia. 

 Capsules opening loculicidally. 

 Flowers in axillary clusters; corolla globose; anthers opening at apex; 



leaves leathery, scurfy beneath. 4. Xolisma. 



Flowers in terminal clusters; corolla ovoid-cylindric; anthers opening 

 lengthwise; leaves membranous, smooth. 5. Oxydendrum. 



Fruit fleshy, indehiscent, berry-like or drupe-like. 



Ovary 5-celled, the cells many-ovuled; fruit many-seeded. 6. Arbutus. 



Ovary 4- to lO-celled, the cells i-ovuled; fruit 4- to lo-seeded. 7. Arctostaphylos. 



75° 



