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dehiscence the valves remain attached only at one point at the 

 top of the connective, and, hinged on this point, each valve 

 gradually rises up, pulling out, as it does so, most of the pollen, 

 which remains attached to its inner surface. Fig. 5 (b). Each 

 valve after rising to an almost horizontal position turns its inner 

 surface which is covered with pollen inwards towards the centre 

 of the flower. Fig. 5 (b) and (c). 



In the open flower these pollen-covered valves are protected 

 from the rain and weather by means of the shelter afforded by 

 the curled-in tips of the petals, so that in looking into the ex- 

 panded flower the valves are hidden from sight. Fig. 6. Look- 

 ing again at the open flower we see that each staminal filament 

 widens out at its base so as to come in contact with the neigh- 

 bouring filament on each side of it. Also a little above the base 

 of the filament, on each side of it, there is an oval, orange- 

 coloured, gland which excretes nectar, two of these so-called 

 nectaries being situated near the base of each petal on its upper 

 surface. Figs. 6 and 7. Each staminal filament fits in closely 

 between two nectaries and, as already noted, lies with its back 

 closely pressed against the surface of the petal. The nectar 

 excreted by the nectaries flows over the base of the filaments 

 and forms a glistening ring around the base of the ovary. The 

 bell-shaped flowers of this plant are either horizontal, or they 

 hang downwards, and the sepals and petals effectually prevent 

 rain from entering the flower and damaging the nectar, or 

 pollen. It will also be noted that as the petals have their tips 

 curled in to protect the pollen they are not so conspicuous as 

 they would be if they were fully expanded, but to compensate 

 for this and to make the flower more noticeable, the three inner 

 sepals are much enlarged and coloured bright yellow. Fig. 6, 

 If now the base of one of the filaments in the expanded flower is 

 touched with a pointed instrument such as a thin pencil, the 

 stamen, with a sudden spring, flies up from its sheltering petal 

 and resumes the erect position it occupied in the unexpanded 

 bud. The pollen- covered valves are thus brought into violent 

 contact with the pencil, but when the latter is removed it will 

 be seen that the valves are not near enough to the centre of the 

 flower to actually touch the stigma. Fig. 8. 



A bee, searching for nectar with its proboscis and touching 

 the irritable base of one of the filaments, will thus cause the 

 stamen to spring inwards and dust with pollen that side of its 

 head which is turned away from the stigma. The insect being 

 struck by the stamen will often fly away at once and after 

 visiting a few flowers its head will be dusted all over with 



