GENUS 12. 



SAXIFRAGE FAMILY. 



225 



throat of the calyx. Stamens 5, inserted with the petals. Ovary i-celled; styles 2, slender. 

 Ovules oo. Capsule 2-valved, 2-beaked. Seeds minutely hispid or muricate. [Named for 

 Johann Heinrich von Heucher, 1677-1747, a German botanist.] 



About 70 species, natives of North America and Mexico. Type species : Heuchera americana L. 

 Flowers regular or nearly so. 



Petals with long very slender claws and narrow blades, much exceeding the calyx. 

 Leaves, at least the larger ones, low rounded lobes. 



Petioles villous ; calyx-lobes ovate, much shorter than the hypanthium during anthesis. 



i. H. parviflora. 

 Petioles puberulent ; calyx-lobes broadly ovate, as long as the hypathium during anthesis 



or nearly so. 2. H.puberula. 



Leaves, at least the larger ones, with prominent angular lobes. 



Leaves deeply lobed, the terminal lobe longer than wide. 3. H. villosa. 



Leaves not deeply lobed, the terminal lobe broad and short. 4. H. macrorhiza. 



Petals with short claws and broad blades, shorter than the calyx or slightly longer. 



Petals as long as the calyx or shorter. 5. 'H. americana. 



Petals decidedly longer than the calyx. 6. H. Curtisii. 



Flowers very irregular. 



Stamens long-exserted. 7. H. hirsuticaulis. 



Stamens slightly exserted or included. 



Flowering stem leafless ; flowers gibbous below near the base. 



Panicle narrow, strict ; stamens exserted. 8. //. hispida. 



Panicle wide, lax ; stamens included. 9. H. longiflora. 



Flowering stem leafy; flowers not gibbous. 10. H.pubescens. 



i. Heuchera parviflora Bartl. Rugel's 

 Heuchera. Fig. 2173. 



Heuchera parviflora Bartl. Ind. Sem. Hort. 



Gotting. 1838. Linnaea 13: Litt. 96. 1839. 

 H. Rugelii Shuttlw. ; Kunze, Linnaea 20 : 43. 



1847. 



Stems slender, 6'-2^' long, weak, glandu- 

 lar-hirsute or villous, 'leafless or bearing a 

 few leaves below. Basal leaves with long 

 slender glandular-villous petioles, broadly 

 reniform, 2'-$' wide, cordate at the base, 

 with 7-9 broad rounded or rarely pointed 

 lobes, crenately toothed, the teeth mucronate; 

 inflorescence very loosely paniculate ; flower- 

 ing calyx regular, campanulate, about i" 

 long; petals linear-spatulate, 2-3 times as 

 long as the calyx-lobes ; stamens somewhat 

 exserted. 



Shaded cliffs, Missouri and Illinois to west- 

 ern Virginia and northern Georgia. July-Sept. 



2. Heuchera puberula Mackenzie & Bush. 

 Puberulent Heuchera. Fig. 2174. 



H. puberula Mackenzie & Bush, Rep. Mo. Bot. Card. 16 : 

 103. 1905. 



Stems very slender, 4'- 12' long, puberulent, leaf- 

 less. Basal leaves with very slender puberulent 

 petioles, suborbicular to reniform, i'-2j' wide, shal- 

 lowly or deeply cordate at the base, with 5-9 rounded 

 lobes and broad mucronate teeth, finely pubescent 

 on both sides ; inflorescence lax, few- or many- 

 flowered; flowering calyx regular, campanulate or 

 turbinate, _ about i" long, the lobes broader and the 

 tube relatively shorter than in H. parviflora; petals 

 spatulate or linear-spatulate, about twice as long as 

 the calyx-lobes; stamens exserted. 



On bluffs, Kentucky and Missouri. July-Oct. 

 15 



