250 FLOWERS AND THEIR WORK. 



12. Describe the inflorescence of a Daisy and of a Dead-nettle, point- 

 ing out the features of (a) resemblance, (6) difference, existing between 

 them. 



13. Describe the process of pollination in any two of the following : 

 Larkspur, Willowherb (JEpilobium), Dead-nettle, Willow. 



14. Describe the flowers of the Primrose, and explain the adaptations 

 for pollination. 



15. What is heterostylism, and what is its importance? Give exam- 

 ples of heterostyled British plants. 



16. Mention any flowers you know which are pollinated by the wind. 

 Describe the structures involved in pollination in each case, and show 

 how they differ from the corresponding structures in insect-pollinated 

 flowers. Have you noticed any other features of wind-pollinated 

 flowers, such as habitat or time of flowering, which you can connect 

 with wind-pollination ? Give instances. 



17. Name three flowers you have seen visited by flies and three by 

 butterflies and moths. How did the insects behave in each case ? 



18. Name three flowers fertilised by bees in which the essential 

 organs of the flower come into contact with the back of the bee, and 

 three in which they come into contact with its underside. Why are 

 bees on the whole better agents of pollination than other insects ? 



19. Describe fully the differences between insect-pollinated and wind- 

 pollinated flowers, and mention six examples of each class. Are the 

 seeds of wind-pollinated flowers generally distributed by the wind or 

 not ? Discuss examples. 



20. What plants may be found flowering (either commonly or 

 occasionally) in the winter months in England out of doors ? 



21. What trees occurring commonly in England have flowers which 

 are visited by insects ? You may take examples both from native and 

 from introduced species. 



22. Mention three examples of plants which possess dimorphic 

 flowers. Give a short description of each illustrated with sketches. 



23. Give a synoptic outline of a lesson on the structure of the 

 gynaecium. State definitely what material you would select for 

 illustration, explaining the special point of interest connected with 

 each specimen. 



24. Draw a flower of violet or pansy as seen in median vertical 

 section. Distinguish between any three wild species of the genus 

 Viola you know. 



25. Give examples of flowers which produce honey, and explain 

 exactly where the honey is produced. Of what use is it to the plant ? 



26. What do you understand by a "typical" flower? Compare 

 briefly the arrangements of the parts in a floral and a vegetative shoot. 



