Climbing Plants and Pla7it Migrations 93 



to right, or away from the sun. Growing on the open veld 

 as they do, their support is seldom long enough for their 

 entire length, but the stems often twine several together in 

 a strand firm enough to bear their weight of pretty blossoms 

 up into the sunlight. You may watch them in the school- 

 room, if you place them in water, and see how at different 

 hours of the day the stems point in 

 different directions. The tips of 

 the stems make wide sweeps, but 

 as they extend in length the coil 

 tightens around the support. One 

 keen-eyed student says she can 

 tell from what hillside Microlovia 

 has been gathered by the plant it 

 entwines. On one hillside she 

 seeks it on Rcstiacax ; in another 

 locality it twines about the rigid 

 branches of Montiuia acrls ; while 

 elsew^here it mingles its scarlet waxy 

 flowers with the hoary heads of 

 Eriocephalus. 



Tendril Climbers. — The pea 

 family, Gre?iadilla and other plants, 

 climb by tendrils. The pumpkin, 

 cucumber, and calabas seldom make 

 use of their tendrils. Their heavy 

 fruits would be a great strain on 

 the plants ; but several native rela- 

 tives, Lufifa and Lagenaria, wdth 



their lighter fibrous fruits, are climbers, and Gerrardanthiis 

 megarhiza of Natal climbs to the tops of highest trees. 



The tendrils of the pea are formed from the upper leaflets 

 of a compound leaf. This use of the leaf throws the responsi- 

 bility of making food upon the stipules or upon the broad- 

 winged stem. In the grape vine the main stem turns aside 

 to form the tendril for climbing and bearing the fruit, while 

 the tendrils of Clematis are formed from the petioles. What is 

 the tendril of the Grenadilla? 



Fig 



95- 



The first leaf of the 

 branch in the pumpkin family 

 changes into a tenvlril. 



