TILIACE^. 171 



ORDER XVIIL— TILIACE^. 



Trees, shrubs, or rarely herbs. Leaves alternate (rarely oppo- 

 site), varying in the arrangement of the nerves and amount of 

 division. Stipules usually small and deciduous (more rarely 

 large and persistent) or absent. Tlowers regular, generally 

 perfect, axillary or terminal, usually cymose. Cymes sometimes 

 solitary, or disposed in panicles. Sepals 5 (rarely 3 or 4), 

 free or coherent, usually valvate in ajstivation. Petals generally 

 as many as the sepals, sometimes absent. Stamens numerous, 

 sometimes separated from the petals by the enlargement of the 

 torus on which they are placed, free (or more rarely with the 

 filaments united), and mono- or poly-adelphous. Anthers 2-celled. 

 Torus small or enlarged. Ovary free, sessile upon the torus, 2- 

 to 10-celled. Style entire, or more or less deeply divided into as 

 many cells as there are lobes in the ovary; sometimes absent, so 

 that the stigmas are sessile. Placentae in the interior angle of 

 the carpels, 1, 2, or numerous, anatropous or sub-anatropous. 

 Fruit dry, drupaceous or berry-like, and indehiscent ; or dividing 

 into cocca, or splitting into as many valves as there are carpels, 

 in which case the dehiscence is commonly loculicidal. Seeds with- 

 out an arillus, with the testa generally hard or leathery, some- 

 times pilose. Albumen fleshy (rarely absent). Embryo commonly 

 straight. Cotyledons often broad and foliaceous ; the radicle near 

 the hilum. 



All the British species belong to the tribe Tiliese, which has 

 the sepals distinct, the petals coloured, not foveolated, with imbri- 

 cated and often contorted testivation, and the torus small, so that 

 the stamens are inserted close to the petals. 



GENUS I.—T ILIA. Zinn. 



Sepals 5, fi'ee, coloured, deciduous. Petals 5, in some of the 

 species with petaloid scales on the inner side. Stamens indefinite, 

 irregularly polyadelphous, all antheriferous. Ovary 5-celled, with 

 2 ovules in each cell. "Style simple, with the stigma 5-lobed. 

 Eruit commonly crustaceous, sub-globular or ovoid, with 3 to 5 

 more or less distinct ribs, 1-celled by the disappearance of the 

 partitions, and 1- or 2-seeded by abortion of the other ovules. 



