THE ANGIOSPERMAE 



1333 



at this stage will settle on the corolla and, while thrusting its tongue into the 

 flower, will receive pollen on its head. Later, as the flower matures, the 

 style elongates till it reaches the level of the anthers, the three stigmatic 

 surfaces diverge and in this stage will receive pollen from a visiting insect. 

 Self-pollination may occur if the divergent stigmas pick up any remaining 

 pollen, for they curve further backwards after opening out, though usually 

 by that time no pollen is left in the flower. As a result of cultivation a 

 number of different coloured varieties have been produced, but they are 

 mainly pink, red or purple in colour, though white forms also occur. 



[b) Moth Flowers 



Flowers which are pollinated by moths are divisible into two types, 

 those which are visited by day-flying moths, which are almost exclusively 

 Hummingbird Hawk Moths, and those which are visited at dusk, which 

 attract various other kinds of moths as well. Flowers belonging to the first 

 type are often brightly coloured, as for example the flowers of Lavandula, 

 while those of the second class are generally white. Both types usually 

 emit a powerful scent and in the latter type the scent is most noticeable in the 

 evening. 



(fl) Flowers opening by day. Among those moth flowers which open by 

 day are Lavandula, Lilium martagon, Lonicera (Fig. 1244), and various species 

 of Cacti, but the number is small compared to those which open at night, 



Fig. 1244. — Lonicera periclynuiiiun. Hawk Moth pollinating a flower, from which part of the 

 corolla tube has been previously cut away to show the penetration of the long proboscis. 

 (Electronic flash photograph by Father Webb, Ampleforth.) 



