HETEROSPATHE 



HEUCHERA 



1481 



elata, Scheff. (Metroxylon datum, Hort.). Tall, 

 unarmed: Ivs. terminal, long-petioled, equally pinna- 

 tisect; segms. numerous, lanceolate, narrowed at both 

 ends, acuminate, 1-nerved, margins thickened and 

 recurved at the base; rachis round on the back, flat on 

 the face; sheath short, fibrous, swelled at the base: 

 spathes 2, the lower 2-crested, the upper much longer. 

 A very worthy palm, valuable chiefly for its graceful 

 habit while still quite young. Must be grown in a 

 moist hot house. N. TAYLOR.! 



HETEROTOMA (name refers to the unequally cut 

 corolla). Campanulacese. About 10 species of Mexican 

 annuals and perennials, one of which has come some- 

 what into cult. Lvs. alternate: fls. blue, yellow or 

 orange, in terminal racemes; calyx tubular with an 

 unequally 5-parted limb, the 2 anterior lobes usually 

 adnate to the spur of the corolla; corolla-tube split to 

 the base on the back, in front produced into a hori- 

 zontal or deflexed spur, the limb short and incurved 

 and with either nearly equal or unequal lobes; stamen- 

 tube free from corolla; ovary inferior, 2-celled, many- 

 ovuled: caps. 2-valved. H. lobelioides, Zucc. Erect, 

 branching, the st. pubescent: Ivs. alternate, ovate- 

 lanceolate, distantly toothed, acuminate: fls. about 2 

 in. long, single on slender axillary peduncles, odd; 

 corolla-spur blood-red, the limb golden yellow and 3- 

 lobed; lower lip of calyx adnate to the corolla-tube 

 and the 2 subulate green lobes projecting beyond it; 

 staminal column erect, as long as the corolla-limb, and 

 prominent. Mountains in Mex. and Cent. Amer. B.M. 

 7849. R.H. 1905, p. 9. An interesting showy perennial, 

 sometimes called "bird flower," to be grown in a cool 

 greenhouse in winter and in the open in summer. 



L. H. B. 



HETEROTRICHUM (name refers to the variable 

 hairs on the Ivs.). Melastomacese. Ten or a dozen 

 hispid, or glandular shrubs in Trop. Amer., with white 

 or pink fls. in terminal or lateral panicles; calyx cam- 

 panulate or globular, with 4-8 teeth; corolla of 6-8 

 petals; stamens 8-12 or more: Ivs. large, ovate or oblong, 

 cordate at base, entire or toothed. H . mdcrodon, Planch., 

 is sometimes mentioned in horticultural literature. A 

 very handsome shrub, 7-9 ft., flowering when small: Ivs. 

 opposite, large, the 2 in the pair unequal, cordate-ovate, 

 abruptly acuminate, serrate, 7-nerved: fls. 10-12 in a 

 terminal cyme, white with red at base of petals, 1 % in. 

 across, the 8 petals obovate and flat-spreading; calyx 

 and young parts hispid or villous. Venezuela. B.M. 

 4421. G.W. 14, p. 652. Requires hothouse treatment. 



L. H. B. 



HEUCHERA (Johann Heinrich von Heucher, 1677- 

 1747, professor of botany at Wittenberg). Saxifragaceae. 

 Herbs resembling the dainty wild flower, the bishop's 

 cap (Mitella) in their habit, as they have a tuft of 

 heart-shaped, five- to nine-lobed, crenate leaves, from 

 which spring a dozen or so slender scapes a foot or more 

 high with small flowers borne in panicles, giving a 

 delicate and any effect. This includes H. sanguinea 

 which probably ranks among the best low perennials 

 with small, red flowers. It is very desirable for the 

 hardy border, where it blooms from spring to late fall. 

 It is also useful to florists for cut-flowers and autumn 

 forcing. 



Heuchera belongs to a group of genera including 

 Mitella and Tiarella, in which the ovary is 1-celled. 

 There is a well-developed hypanthium often bell- 

 shaped, sometimes urceolate, cylindrical, turbinate, or 

 saucer-shaped, often more or less oblique, and adnate to 

 the lower part of the pistil. Most of the distinguishing 

 characters of this difficult genus are found in the shape 

 of the hypanthium. In Heuchera the petals are 5 or 

 none, and entire; in Mitella 5, 3-fid or pinnatifid; in 

 Tiarella 5 and entire. Heuchera has 5 stamens; Mitella 

 5 or 10; Tiarella 10. The caps, of Heuchera is inferior, 



2-beaked; in Mitella superior, not beaked; in Tiarella 

 superior, compressed. Heuchera has 72 species, all 

 N. American and ranging from Mex. to the arctic 

 regions. A full botanical treatment is by P. A. Ryd- 

 berg, in N. Amer. Flora. 22:97-117 (1905), which has 

 been followed in the account below. Many of the 

 species are distinguished only by rather technical 

 botanical characters, but only a few of them are 

 known horticulturally. 



The attractive and petal-like part of H. sanguinea 

 is the calyx, the petals being small in all heucheras 

 (often shorter than the calyx). The other species are 

 attractive by reason of their general habit, and particu- 

 larly the graceful, open panicle. H. sanguinea came 

 into prominence about 1884 and is now deservedly 

 one of the most popular of hardy perennials. The 

 others are procurable from the largest dealers in 

 native plants and from western collectors. They range 

 from 3 inches to 3 feet high, averaging about 13^ feet, 

 and bloom in summer, having greenish white or purplish 

 flowers. Almost any good garden soil suits them, and 

 they are not particular as regards exposure to sunlight 

 (though an open situation is preferable) ; and they look 

 well in borders, rockeries, separate beds and elsewhere. 

 Propagate by division or seed. 



alba, 10. 

 americana, 3. 

 braeteata, 7. 

 brizoides, 10. 

 cylindrica, 9. 

 erubescens, 2. 

 gracillima, 10. 

 grandiflora, 10. 



INDEX. 



hispida, 6. 

 hybrida, 10. 

 maxima, 10. 

 micrantha, 2. 

 parvifolia, 8. 

 pubescens, 5. 

 ribifolia, 5. 



robusta, 10. 

 rosea, 10. 

 rubescens, 4. 

 rubifolia, 5. 

 sanguinea, 10. 

 splendens, 10. 

 villosa, 1. 



KEY TO THE SPECIES. 



A. Stamens equaling or exceeding the 



sepals. 

 B. Panicle open, not spike-like. 



c. Hypanthium not strongly ob- 

 lique. 

 D. Breadth af hypanthium about 



as the length. 

 E. Lobes of the If. -blade broadly 



triangular, acute 1. villosa 



EE. Lobes of the basal If. -blades, 



at least, rounded. 

 p. The hypanthium, with the 



sepals 1-1 Yi lines long. . . 2. 

 PP. The hypanthium, with the 



sepals 1^2~4 lines long. . 3. 

 DD. Breadth of hypanthium about 



twice the length 4. 



cc. Hypanthium strongly oblique; 

 stamens equaling or slightly ex- 

 ceeding the sepals. 

 D. Flowering branches more or less 



leafy 5. 



DD. Flowering branches leafless or 



practically so 6. 



BB. Panicle dense, contracted, almost 



spike-like 7. 



AA. Stamens much shorter than the sepals. 

 B. Hypanthium and sepals l}^2}^ 



lines long 8. 



BB. Hypanthium and sepals 2%-5 lines 

 long. 



c. Infl. contracted and spike-like 9. 



cc. Infl. open, not spike-like 10. 



micrantha 

 americana 

 rubescens 



pubescens 



hispida 



braeteata 



parvifolia 



cylindrica 

 sanguinea 



1. villfisa, Michx. Height 1-3 ft.: If .-blades nearly 

 round, deeply 5-7-lobed, the lobes triangular acute: 

 scape mostly leafless; calyx and hypanthium about 

 1 line long; petals pinkish, twice as long as the sepals. 

 Rocky places, Va. to Ga. and Tenn. B.B. 2:179. A 

 good border plant. 



2. micrantha, Douglas. Height 1-2 ft., the flowering 

 branches 1-4-lvd. or almost scape-like.: Ivs. slightly 

 hairy, the blades round-cordate, about as long as broad, 

 long-stalked: infl. glandular-hairy; petals oblanceolate, 

 whitish, not very showy. Calif, to Brit. Col. B. R. 



