232 STUDY OF COMMON PLANTS. 



surface of stems, leaves, flowers, and fruit, first with the 

 naked eye, and then with a good lens. Imagine a soft- 

 bodied animal attempting to crawl up to the leaves or 

 flowers. Which parts are best protected ? 



Tendrils. 



I. Study carefully the tendrils, noting particularly their 

 origin, form, and mode of grasping a support. How do 

 they compare in their subsequent behavior with those of 

 bryony, described by Sachs ? 1 



II. Rub one of the young tendrils and watch it for a 

 few minutes. Is there any movement? Does it make 

 any difference whether the concave or convex side is 

 rubbed ? 2 



III. Watch a vigorous specimen long enough to observe 

 the spontaneous movements of its tendrils. 



Inflorescence and Flowers. 



I. How many flowers compose the inflorescence? Are 

 they all alike ? Compare those in the axils of the lower 

 leaves with the ones produced higher up. Is this species 

 monoecious or dioecious? 3 



II. Examine carefully the stamens, noting the form 

 and structure of the anthers and their peculiar mode of 

 cohesion. 4 



III. How many stigmas are there ? Examine their sur- 

 face with a lens. 



IV. Are there any nectaries ? How far do the flowers 

 of the cucumber agree with those of Bryonia dioica, as 



1 Physiology of Plants, pp. 663, 664. 



2 Cf. Darwin, Climbing Plants, p. 127 et seq. 



3 Cf. Gray, Lessons, p. 85. 



* Cf. Goebel, Outlines of Classification and Special Morphology, p. 357. 



