QUESTIONS. 305 



3. At what hour does it open its flowers? 



4. How long do they remain open? When do they close? 



5. Do they open and close more than once ? 



6. Do the leaves change position at night, or in shade ? 



7. Describe the change. 



S. How is the nectar affected by the flowers' closing? 



§ 3. Irritability. 



1. Is this plant sensitive to touch? In which organj 



2. How is this indicated ? 



§ 4. Movements. 



1. How is this vine furnished for climbing? 



2. Has it any special organs ? What are they ? 



3. Have you observed their movements ? Describe them, 



4. What seems to be the purpose of this motion ? 



5. After it has reached an object, how does the tendril aci? 



6. How does a vine without tendrils climb ? 



7. Is it aided by its petioles ? Explain. 



8. If it be a twining vine, which way does it turn ? 



9. To find a support, what movement have you observed? 

 10. Is it aided by hairs, or prickles ? — by rootlets? 



§ 5. Classification. 



1. Is this plant an Exogen, or an Endogen? 



2. By what marks do you determine this? 



3. Has it a stigma, and a seed-vessel ? Is it then a Gymnosperm? 



4. Have you determined its Order ? — its Genus ? — its Species ? 



