142 THE BOOK OF NATURE STUDY 



but can also be inferred from the presence of a sepal in the middle 

 line behind since the petals alternate with the sepals. The 

 corolla is easily removed, and, looked at from the side, shows a 

 narrow tubular portion at the base. Above this it widens out 

 suddenly into a sort of pouch in front, and continues to widen 

 slightly until it divides into the two lips described above. When 

 split open, or in a flower cut in half, a number of white hairs will 

 be found blocking the corolla tube just where the narrow part 

 at the base ends (Fig. 23, c). The whole corolla is of a yellowish 

 white tint. 



There are four stamens, not five as might have been expected. 

 The stamen which should stand in the middle line behind is absent. 

 The stamens are joined on to the corolla, and their attachment 

 will be seen on slitting up a corolla in the middle line behind and 

 spreading it out. The two stamens, which are attached farther 

 forward in the flower, have longer stalks than the other two, and 

 their anthers stand in front of those of the other pair. All four 

 anthers lie beneath the upper lip of the corolla, which protects 

 them from wet, and they face downwards. The pollen does not 

 drop out of the open anthers. 



The style is also bent backwards, and lies between the stamens 

 beneath the upper lip of the flower. It ends in a two-lobed 

 stigma, one branch of which is directed forwards and the other 

 backwards. The inner surface of these lobes is the receptive 

 one for the pollen. Usually the style, being entangled among 

 the stamens, is pulled off when the corolla is removed, but some- 

 times it can be left in position. It is then seen to spring from 

 the centre of four green lobes, which are visible on looking into 

 the cup-like calyx. These are the four lobes of the ovary, which 

 is not, however, composed of four carpels but, as the two-lobed 

 stigma indicates, of two. Each of these is subdivided into two 

 chambers, and in each of the four cavities thus formed is a single 

 ovule. If the calyx is carefully split open with the point of the 

 knife, and peeled away from the ovary, two delicate whitish 

 yellow scales will be seen lying against the front of the latter, 

 and springing from beneath it. These are the nectaries, and 

 the nectar accumulates in the narrow lower part of the corolla 

 tube protected by the ring of hairs. 



