174 FIEST STUDIES IN PLANT LIFE 



XX. — More About the Flowers' Debt to Insects. — P. 118. 

 1-2. Honey -guides. 3-5. Hairs and sticky patches act as 

 guards to the honey. 6. The different position of the honey -stores 

 in diflfereiit plants. 7-8. The charm and the mystery of scent. 

 9-11. The colour of flowers : stamens become petals that grow gay 

 in colour ; yellow, pink, purple, blue, white. 12. How the bees 

 paint flowers. 13. An increase of bees may give gayer colours to 

 our native flowers. 



XXI.— Wind-fertilized Flowers.— P. 125. 



1-2. The oak uses the wind to scatter its seed over the tree. 

 3. The poplar has the pollen flowers on one tree, the pistil flowers 

 on another. 4. The pollen is generally made and scattered before 

 the leaves come out. 5-6. How the common plantain scatters its 

 seed. 7-8. The wheat and maize plants. 



XXII.— How Seeds are Spread.— P. 130. 



1-2. Only a small proportion of seeds become plants. 

 3. Krakatoa was restocked with plants by winds, waves, and 

 birds. 4-6. Some plants jerk their seeds out of the fruit : 

 geranium, field-sorrel, gorse, dolichos. 7-8. Wattle and other 

 seeds are spread by water. 9. The coco-nut is carried to distixnt 

 lands by ocean currents. 10. Pondweeds and seaweeds throw off 

 little buds, borne along on the surface of the water. 11. Some 

 grasses bury their seeds by means of bristles or awns. 



XXIII.— How Seeds are Spread by Animals.— P. 135. 



1-3. The sweet, , coloured fruits attract birds and other 

 animals. 4. Colours of fruits and flowers compared. 5-7. Birds 

 spread small seeds in various ways. 8. Sticky seeds : rib-grass, 

 groundsel, laurel, plumbago. 9. Hooked seeds : the burrs. 

 10. Birds may carry seeds in the mud on their legs. 11-12. Man 

 spreads seeds : on boots ; in ships ; in imported seed. 



XXIV.— How Seeds aee Carried by the Wind.— P. 142. 



1. Many high plants are spread by the wind. 2. The tumble- 

 weed. 3. The poppy. 4-5. A balloon of silky hairs is found in 

 damdelion and willow-herb. 6. Trees with hairy seeds : plane, 

 willow-oleander. 7-8. Winged seeds of Cape love-lily, parsnip, 

 hop, pine, elm, sycamore. 9. The gum seed-cases. 10-11. Invis- 

 ible seeds : moss and lichens. 



