132 DICOTYLEDONS 



by the agency of many kinds of insects (bees, beetles, flies, 

 etc.). Self-pollination often takes place in open flowers, 

 because the stigmas come in contact with the anthers ; but it 

 also occurs in flowers which remain closed. These closed self- 

 pollinating flowers are merely ordinary flowers which fail to 

 open ; they are not reduced and altered as are the cleistogamic 

 flowers of the Violet. 



Other Types: PINK {Dianthus): CATCHFLY {Silene): 

 CAMPION {Lychnis). 



The flowers of these plants differ from those of the Chick- 

 weed more particularly in having a tubular gamosepalous calyx 

 and long-clawed petals. Their honey is consequently con- 

 cealed at the bottom of a long tube, and cannot be reached by 

 short-tongued insects. These flowers are exclusively pollinated 

 by insects with long tongues — i.e. mainly by butterflies and 

 moths. The comparison between these flowers and those of 

 Stellaria gives us additional evidence for the view that the 

 shapes of insect-pollinated flowers bear relation to the sorts of 

 insects which pollinate them (see pages 8i, 82 and iig-121). 

 It is important to note that Pinks are pollinated by butterflies 

 flying during the daytime, and that they often have a pink 

 colour and delicious scent. Contrast this with the white 

 colour of the flowers of Lychnis vespertina, which open at 

 dusk, give out their strongest scent at that time, and are 

 pollinated by night - flying moths. The white colour renders 

 flowers more conspicuous at night. 



MALVACEJE (Mallow FamUy) 



Herbs or shrubs. Leaves alternate, stipulate. Flowers 

 regular, hypogynous, often showy. Sepals five, gamosepalous, 

 valvate. Petals five, nearly polypetalous, joined to the stamens 

 at the base. Stamens numerous, filaments united. Anthers 

 with only two pollen-sacs each. Carpels from three to 00, 

 syncarpous (or apocarpous). Ovary with from three to many 

 chambers. 



Type : MALLOWS {Malva sylvestris and M. rotundifolid). 



These two species may be treated together, as they are very 

 similar. 



