762 MALVACEAE 



8. Tilia leptophylla (Vent. ) Small. A tree, resembling T. pubescens in habit, but 

 with relatively smaller, and thin and less copiously pubescent leaf-blades : bracts smaller, 

 4-7 cm. long, almost glabrous beneath or thinly pubescent : flowers and fruit smaller. 



In woods, Louisiana and Texas. Spring. 



FAMILY 2. MALVACEAE Neck. MALLOW FAMILY. 



Herbs, shrubs or rarely trees, of great economic importance, the vege- 

 tative parts destitute of any unwholesome substance. Foliage often pubescent 

 with simple or branching hairs. Leaves alternate, stipulate : blades palmately 

 nerved and often lobed, usually crenate or toothed. Inflorescence axillary, 

 racemose, paniculate or corymbose, sometimes congested. Flowers regular, per- 

 fect, often subtended by an involucre resembling a second calyx. Calyx of 5 

 more or less united sepals, these valvate, mostly persistent. Corolla of 5 hypog- 

 ynous convolute petals, these alternate with the sepals, united : blades often in- 

 equilateral. Androecium of numerous stamens. Filaments monadelphous, united 

 with the claws of the petals. Anthers reniform, 1-celled. Pollen-grains hispid. 

 Gynoecium of several carpels. Ovary several-celled, or the several pistils dis- 

 tinct. Styles terminal. Stigmas capitate. Ovules amphitropous or semianat- 

 ropous, pendulous or ascending, inserted in the inner angles of the cavities. 

 Fruit capsular, or the carpels separate or separable. Seeds solitary or numer- 

 ous, with a crustaceous, smooth or rough sometimes pubescent testa. Endo- 

 sperm scant, fleshy, mucilaginous. Embryo large, curved or folded, with folia- 

 ceous cotyledons. 



Fruit of several radially disposed carpels, which separate from each other at maturity. 

 Carpels as many as there are stigmas. 

 Carpels 2-several-seeded. 

 Carpels 1-celled. 



Carpels leathery or parchment-like, never bladdery. 1. ABUTILON. 



Carpels membranous, bladder-like. 2. GAYOIDES. 



Carpels 2-celled, sometimes imperfectly so. 



Involucel wanting. 3. WISSADULA. 



Involucel of 3 bractlets. 4. MODIOLA. 



Carpels 1-seeded. 



Stigmas decurrent on the inner side of the styles. 



Petals notched at the apex : carpels beakless, without internal processes. 5. MALVA. 

 Petals erose at the apex: carpels beaked, with an internal process 



above the seed. 6. CALLIRRHOE. 



Stigmas terminal, capitate. 



Involucel of 2-3 bractlets. 7. MALVASTRUM. 



Involucel wanting. 8. SIDA. 



Carpels % as many as there are stigmas. 

 Carpels dry, achene-like. 



Involucel wanting : inflorescence capitate. 9. MALACHRA. 



Involucel of several bractlets : inflorescence axillary or racemose. 



Involucel of 5 partially united bractlets : carpels spiny all over. 10. URENA. 



Involucel of 5-15 distinct bractlets : carpels unarmed or with 1-3 spines 



on the back. 11. PAVONIA. 



Carpels forming a drupe-like berry, but separating at maturity. 12. MALVAVISCUS. 



Fruit a loculicidal capsule, or rarely indehiscent. 

 Styles distinct, spreading : seeds usually reniform. 



Capsules as long as broad or much longer, the cavities 2-many-seeded. 13. HIBISCUS. 



Capsules much depressed, the cavities 1-seeded. 14. KOSTELETZKYA. 



Styles united : seeds not reniform. 



Bractlets of the involucels entire, rather inconspicuous. 



Trees : sepals wholly united or nearly so : capsules indehiscent. 15. THESPESIA. 



Shrubby plants : sepals merelv united at the base : capsules loculicidally 



3-5-valved. 16. CIEXFUEGOSIA. 



Bractlets of the involucels laciniate, conspicuous. 17. GOSSYPITM. 



1. ABUTILON Gaertn. 



Herbs, shrubs or rarely trees, with softly pubescent foliage and branching stems. 

 Leaves alternate : blades entire, toothed, angled or lobed, usually cordate at the base. 

 Flowers perfect, mostly axillary. Involucel wanting. Sepals 5, united below. Petals o, 

 of various colors, often yellow, distinct. Carpels 5-30. Styles filiform or club-shaped. 

 Stigmas terminal. Ovules 3-9 in each cavity. Carpels 1-celled, leathery or parchment- 

 like, not bladdery, disposed about a central axis, more or less prominently beaked, 2-valved 



