THE BINDWEED FAMILY 85 



carried away to a great distance with the seed attached to it 

 beneath. Compare this pappus with that found in some Compo- 

 sites (page 70). In this case the silk floss is formed inside the 

 carpel, whereas in the Composites it is a growth on the top of 

 the carpels. 



4. Most of the other Asclepiadaceae are climbers. One of 

 them, Hemidesmus indicus (Kan. Namadaberu; Mai. Nannari; 

 Tarn. Nannari; San. Bhadravalli), affords the so-called Indian 

 Sarsaparilla. Daemia extensa (Kan. Juttuve, Pettatajank; Tatn. 

 Belaparti) is very common and possesses cordate leaves and 

 greenish flowers. 



20. The Bindweed Family 



(Convolvulaceae). 



Herbs, rarely shrubs mostly twining, with alternate, exstipulate 

 and usually cordate leaves. Mostly twiners. Many with milky juice. 

 Inflorescence cymose. Flowers radial. Corolla funnel-shaped, folded 

 inwards (induplicate) and twisted (convolute) in bud. Stamens five, 

 epipetalous, often of unequal lengths. Ovary superior, of two carpels, 

 usually with two large seeds in each cell. Seed endospermous. 

 Cotyledons folded. 



The Elephant Climber (Argyreia speciosa). 



{Kan. Samudrapala. Mai. Samudrajogara.) 



This is a huge climber, commonly found in thickets and 

 jungles, especially near the sea. Stem and lower side of leaves 

 covered with white, silky hairs. Leaves large and cordate. We 

 choose this plant as a type of the lianas, a name given to climb- 

 ing and winding plants in tropical forests. 



1. Why the Elephant Climber climbs. — Plants cannot live 

 without light. If we grow any plant in a flower-pot and keep it 

 in a room, it- will invariably stretch its branches towards the 

 window, eagerly seeking the light. If it cannot get suthcient 

 light, it will etiolate, i. e., grow white from absence of the 

 normal amount of chlorophyll in its leaves, and the stalks be- 

 come unnaturally long, producing small and bent leaves, but no 



