MALVACEAE. 617 



Leaves glabrous or nearly so on both surfaces. I. T. Americana, 



Leaves glabrous above, pubescent beneath. 2. T. pubescens. 



Leaves glabrous above, silvery-white beneath. 3. T. heterophylla. 



i. Tilia Americana L. Bass-wood. American Linden. White- wood. 

 (I. F. f. 241 1.) A forest tree with spreading branches. Leaves ovate, 5-13 cm. 

 wide, coriaceous, sharply serrate with glandular teeth, abruptly acuminate or acute; 

 floral bracts 5-10 cm. long, strongly veined; cymes drooping, 6-20-flowered; flowers 

 1-1.4 cm. broad, fragrant; petals yellowish white, crenate, slightly longer than the 

 pubescent sepals; scales similar to the petals, but smaller; fruit globose-ovoid, 8-10 

 mm. in diameter. In rich woods and along river-bottoms, N. B. to Ga., Manitoba, 

 Neb. and Tex. May-June. 



2. Tilia pubescens Ait. Southern Bass-wood or White-wood. (I. F. f. 

 2412.) A small tree. Leaves generally smaller than those of T. Americana; floral 

 bracts commonly broader and shorter ; fruit globose, 5-6 mm. in diameter. In 

 moist woods, L. I. to Fla., west to Tex., mostly along the coast. May-June. 



3. Tilia heterophylla Vent. White Bass-wood. Bee-tree. (I. F. f. 

 2413.) A forest tree. Leaves larger than in either of the preceding species (often 

 1.5 to 2 dm. long), dark green above, acute or acuminate ; floral bracts 7.5-12.5 

 cm. long, narrowed at the base ; flowers slightly larger and often fewer than those 

 of T. Americana; fruit globose, about I cm. in diameter. In woods N. Y. to Fla., 

 Ala., 111., Ky. and Tenn. June-July. 



The European Linden, or Lime Tree, Tilia Europaea L., is planted as an orna- 

 mental tree in parks and on lawns. It may be distinguished from any of our species by 

 the absence of scales at the base of the petals. Its name, Lin, was the origin of the fam- 

 ily name of Linnaeus. 



Family 2. MALVACEAE Neck. 



Mallow Family. 



Herbs or shrubs (sometimes trees in tropical regions), with alternate 

 leaves. Stipules small, deciduous. Flowers regular, usually perfect, 

 often large. Sepals 5 (rarely 3 or 4), more or less united, usually val- 

 vate ; calyx often bracted at the base. Petals 5, hypogynous, convolute. 

 Stamens 00 , hypogynous, forming a central column around the pistil, 

 united with the bases of the petals; anthers i-celled. Ovary several- 

 celled ; styles united below, distinct above, and generally projecting 

 beyond the stamen-column, mostly as many as the cavities of the ovary. 

 Fruit capsular (rarely a berry), several-celled, the carpels falling away 

 entire or else loculicidally dehiscent. Seeds reniform, globose or obovoid ; 

 embryo curved; cotyledons large, plicate or conduplicate. About 40 

 genera and 800 species, widely distributed. 



Stamen-column anther-bearing at the summit. 

 Carpels i-seeded. 

 Flowers perfect. 



Involucels of 6-9 bractlets. I. Althaea, 



Involucels of 1-3 bractlets, or none. 



Stigmas linear, on the inner side of the style-branches. 



Carpels beakless; petals obcordate. ' 2. Malva. 



Carpels beaked; petals truncate. 3. Callirrhoe. 



Stigmas capitate, terminal. 



Seed ascending. 5. Malvastrum, 



Seed pendulous. 6. Sida. 



Flowers dioecious. 4. Napaea. 



Carpels 2-several-seeded. 



Involucels none. 7. Abut Hon, 



Involucels of 3 bractlets. 



Carpels continuous. 8. Sphaeralcea. 



Carpels septate between the seeds. 9. Modiola. 



Stamen-column anther-bearing below the entire or 5-toothed summit. 



Carpels 1 -seeded. 10. Kosteletzkya. 



Carpels several-seeded. 11. Hibiscus. 



