596 



BOTANY 



PART II 



Order 14. Columniferae 



The essential character of this order is afforded by the androecium 

 of the regularly pentamerous, actinomorphic, hermaphrodite flowers. 

 One of the two whorls of stamens, usually the outer one, is sup- 

 pressed or only represented by staminodes, while the other whorl 

 has undergone a greater or less increase in the 

 number of its members by chorisis. The branch- 

 ing is frequently accomi^anied by cohesion of the 

 filaments. The carpels also sometimes exhibit an 

 increase in number as a result of branching. The 

 superior ovary is then divided into a corresponding 

 number of loculi. 



Family 1. Malvaceae. — Herbs or shrubs, fre- 

 Fic 594 — Maiv ceae ^^eutly with palmatcly-lobed, stipulate leaves which 

 Floral diagram (^Maiva). in the young condition often have a velvety cover- 

 ing of stellate hairs. Flowers with an epicalyx, a 

 gamosepalous calyx, and a corolla which is usually of considerable 

 size and attractively coloured, and is contorted in the bud. Pro- 

 tandrous. Stamens united into a tube around the ovary ; the free 

 ends of the stamens, each of which bears a single reniform theca, 

 project from the margin of the staminal tube. Pollen-grains with 



Fio. ."JOS. — Flower of Althaea officinalis, cut 

 through longitudinally. a, Outer ; b, 

 inner calyx ; c, petals ; (/, androecium ; /, 

 pistil; e, ovule (magnilicil). (After Bero 

 and ScHMTDT.) 



Firi. ^OG.—Malrasihrstris. o, Flower; 

 b, flower-bud ; c, fruit (nat. .size). 



spiny exine (cf. Fig. 429). Carpels usually numerous. Fruit a 

 schizocarp or a capsule (Figs. 594-597). 



Generally distributed, especially in the tropics. 



Important Sub-families and Genera. —1. J/aZi'e«e.— Schizocavps composed 

 of numerous carpels, arranged in a circle. Malva, with a number of Britisli species 



