THE AXGIOSPERMAE 



1335 



pollen from another flower. In the later stage the anthers split longitudi- 

 nally so that the moth visiting the flower will now receive pollen on its 

 wings. Automatic self-pollination is possible in the later stage of anthesis, 

 because pollen from the mature anthers may fall on the stigma which hangs 



below them. 



(b) Flowers opening by night. Among the flowers pollinated by night- 

 flying moths, one of the best-known examples is Nicotiana. N. affints is 



Fig. 1246. — Nicotiana affinis. A, Part of inflorescence. B, 

 Young state with stigma presented at mouth of the floral 

 tube. C, Later stage with stigma withdrawn and anthers 

 presented. 



commonly cultivated and both red and white forms are known in gardens 

 (Fig. 1246). The white flowers are readily pollinated by night-flying moths, 

 but the red form is not so commonly visited since it is less visible at night. 

 Both, however, emit a strong scent w^hich is most highly developed in the 

 evening. The five-parted tubular calyx is quite short, but the corolla tube is 

 exceptionally long, sometimes 50 mm. or more. It terminates in five divergent 

 limbs. There are five stamens which arise from the base of the corolla tube and 

 have very long filaments and small rounded anthers. The ovary lies at the 

 base of the corolla tube and bears a very long, slender style with a capitate 



K* 



