208 GENERAL BOTANY 



depending as it does on its function, may be different 

 from the normal, but by its position on the plant in 

 relation to other organs. 



In many cases the sepals or calyx are coloured 

 although the corolla is present, as, for instance, in 

 DELPHINIUM, the Monk's hood, MICHELIA the Cham- 

 paca, TROP^EOLUM the Garden-nasturtium, C^ESAL- 

 PINIA PULCHERRIMA, CASSIA FISTULA the Indian 

 Laburnum, BEGONIA, HOLMSKIOLDIA, PETR^EA, and 



many other common Indian plants. They then add 

 to the beauty and attractiveness of the flower, which 

 is the chief duty of the petals (see chapter xxi, 

 section 3). 



This is even more the case with MUSSyENDA, a 

 very common shrub on the ghats and hills of South 

 India, up to 6,000 ft. One sepal of the five here grows 

 out like a large white leaf (this is one sign of the leafy 

 nature of sepals), and shows up the dark orange corolla 

 of the corolla very clearly. 



In the case of BOUGAINVILLAEA, the colour of the 

 flower is due to three bracts, which belong each to 

 one of the three small tubular flowers inside, for these 

 flowers have no petals, the perianth being single 

 a tubular calyx only. 



3. In a very large number of plants the calyx tube 

 or cup, surrounds the ovary and is even produced be- 

 yond it, and bears at the top the petals and stamens. 

 The ovary thus stands below the latter and is, therefore, 

 said to be inferior. We can hardly in this case consider 

 the calyx tube as made up of combined sepals, but rather 

 as the deeply hollowed out end of the pedicel, the 

 ovary being in the middle and therefore at the bottom 



