304 Plants and their Ways in South Africa 



slits. 



A. Ovary i -locular ; seeds many, parietal ; anthers opening by 

 r. 



Drosera. — Delicate herbs with a rosette of leaves or a 



leafy stem ; covered with 

 curious " tentacles " ; or 

 stalks ending in swollen 

 purple heads which glisten 

 with a sticky fluid. Flies, 

 mistaking this for honey, 

 are caught fast. The ten- 

 tacles are so sensitive to 

 even a gentle pressure that 

 they curve inward and 

 smother their hapless vic- 

 tim. A fluid in the purple 

 heads digests the food 

 containing nitrogen in the 

 insect's body. This is used 

 by the plant especially in 

 seed-making, although the 

 plants can live without in- 

 sect food. This is why 

 sundews can live in very 

 poor soil which will sup- 

 port nothing else. The 

 Fig. 276.— Drosera cistijlora, L. gg^us is found in all parts 



of the world. 



B. Ovary y locular ; seed one, pendulous, anthers opening by 

 pores, stamens with a sensitive gland. 



Roridula is a branched shrubby plant. The tentacles do 

 not curve over its victim as in Drosera. 



Dr. Marloth has found that the sticky fluid which impales 

 the insects does not digest them. This fact, together with the 

 diff"erences in habit and in floral structure, possibly entitles it 

 to a position in a separate order. 



A spider acts as a scavenger for the plants, removing the 

 insects from the leaves, and is saved the trouble of making a 

 web. Strangely enough the spider can run where the flies 



