THE HIGHER DICOTYLEDONS. 371 



Note the structure of the ripe fruit (akene), opening up 

 the fruit- wall to see the single seed. Note how the parachute- 

 like pappus (ring of hairs) closes up on wet days (why ?) 

 and expands on dry days (why?). By what agency is the 

 seed dispersed ? Try the effect of picking oft' the parachute 

 from the fruit ; note the times taken for (1) a complete fruit 

 with expanded pappus, (2) the same fruit deprived of the 

 pappus, to fall from the same height. Try the comparison 

 under different conditions, e.g. indoors and outdoors, on a 

 still day and on a windy day. Note the small stiff hairs 

 (straight or hooked ?) on the akene itself. How do these hairs 

 help the akene to become attached to the soil after the para- 

 chute comes down ? What are the advantages of having the 

 pappus carried up on a long stalk ? When is this stalk above 

 the ovary developed ? Is there any trace of it in the flower ? 



370. Daisy (Bellis perennis). This familiar plant flowers 

 from spring to autumn; even in winter a few days of 

 sunshine will often cause the flower-buds to open. It is 

 practically evergreen as well as perennial, producing leaves 

 throughout the year. In general habit it resembles the 

 Dandelion, but the stem is longer and it sends out runners 

 all round, giving rise to numerous new plants ; apart from 

 seeds, therefore, the Daisy has a very efficient method of 

 spreading and multiplying. 



Carefully examine patches of Daisies at frequent intervals 

 during the year, making notes (with sketches) of your ob- 

 servations. At what time of year are the " runners " given 

 off by the parent plant most copiously ? How many young 

 plants may be formed in this way ? How long are the 

 runners ? 



Note the arrangement of the leaves in a rosette. Sketch 

 a plant from above, showing the shapes of all the leaves. 

 Where is each leaf broadest ? What are the advantages of 

 the peculiar shape of a Daisy leaf ? Which leaves (upper or 

 lower) have the longest basal parts and the largest blades, 

 and why ? Why is it a good plan for a rosette-forming plant 

 to have its leaves broadest towai-ds their free ends ? 



Examine the flower-heads (Fig. 153) and the individual 

 flowers very carefully, on the lines indicated in the preceding 

 article on the Dandelion. How long are the flowering-axes ? 



