598 



BOTANY 



PART II 



Family 2. Tiliaeeae. — For the most part trees or shrubs, less 

 commonly herbs, with simple, stalked leaves provided with deciduous 

 stipules. Calyx polysepal- 

 ous. Estivation of calyx 

 and corolla valvate. 

 Stamens completely free 

 from one another with 

 introrse anthers. A5 + 5, 

 or only the inner whorl 

 is present and has usually 

 undergone branching (Fig. 

 598). Ovary with two to 

 many loculi, and one to 

 many ovules in each loculus. 

 Style simple. 



Most of the genera are 

 tropica]. The herbaceous 

 species of Corchorus yield Jute. 



Fig. 598 Tiliaeeae. Floral diagram 



(TilUi). (After Eichler.) 



Fig. 699. — Tilia idraifoUa. A, Iiitlorescence (a), wiUi 

 bract ; 6, (nat. size). B, Longitudinal section of 

 fruit (niaf^uitted) ; o, pericarj) ; p, atrophied dissepi- 

 ment and ovule ; q, seed ; /■, endosperm ; »■, embryo ; 

 t, its radicle. (After Berg and Schmidt.) 



Ill Britain two species of Tilia, Lime, occur. These are stately trees with 

 two-ranked, petiolate leaves, the stipules of which are soon shed. Tlie leaves, 

 which have a serrate margin, are asymmetrical. The inflorescence (Fig. 599, A) 



is coherent with a bract for half its length ; this serves 

 as a wing in the distribution of the fruit. A second 

 l)ract at the base j^rotects the axillary bud, which will 

 expand in the succeeding season. Below the terminal 

 tlower are three small bracteoles ; the lowest of these 

 is .sterile while the two uj^per ones have single flowers 

 in their axils. Each of these flowers has a jmir of 

 bracteoles which serve as the subtending leaves for 

 further branching. The umbel-like inflorescence of the 

 Lime is thus composed of dichasia ; Tilia platypliyllos 

 has 3-7, T. parvifolia 11 or more flowers in the inflores- 

 cence. The hairy ovary has two ovules in each of its Ave loculi. The fruit only 

 contains one seed (Fig. 599, B). 



Family 3. Sterculiaeeae. — Tropical herbs, shrubs, or trees, with 



Fig. 600. —8 1 e r c u 1 i a c m a e. 

 Floral <liaj;ram. (Theo- 

 broiii'i.) (After Ek-ht.er.) 



I 



