160 ESSENTIALS OF BOTANY 



very much like leaves, and in many cactuses the bracts 

 about the flower are so sepal-like that it is impossible to 

 tell where the bracts end and the sepals begin (Fig. 117). 

 The same thing is true of sepals and petals in such flowers 

 as the white water-lily. In this flower there is a remark- 

 able series of intermediate steps, ranging all the way from 

 petals, tipped with a bit of anther, through stamens with 

 a broad petal-like filament, to regular stamens, as is shown 



H 



ITiG. 118. Transitions from Petals to Stamens in Wliite Water-Lily. 

 E, F, G, H, various steps between petal and stamen. 



in Fig. 118, E, F, G, II. The same thing is shown in 

 many double roses. In completely double flowers the 

 stamens and pistils are transformed by cultivation into 

 petals. In the flowers of the cultivated double cherry the 

 pistils occasionally take the form of small leaves, and some 

 roses turn wholly into green leaves. 



Summing up, then, we know that flowers are altered 

 and shortened branches : (1) because flower-buds have, as 

 regards position, the same kind of origin as leaf-buds : 

 (2) because all the intermediate steps are found between 

 bracts, on the one hand, and stamens, on the other. 



