72 PINK, LYCHNIS. [CHAP. 



chia, Holosteum, Cerastium, Stellaria (Fig. 62), Sper- 

 gularia, Spergula, and Polycarpon. 



In Dianthus, of which we may take D. deltoides, 

 the Maiden Pink, as an illustration, the stamens 

 are united with the petals at the base, and form a 

 yellow, fleshy, swelling which secretes honey. The 

 tube of the flower is so narrow, and so nearly closed 

 by the stamens and pistil, that the proboscis of 

 Lepidoptera alone can reach the honey, though flies 

 and other insects visit it for the pollen. The upper 

 surface of the flower forms a flat disk, pink or spotted 

 with white. The stamens are ten in number. Soon 

 after the flower opens, five of them emerge from the 

 tube, ripen, and the anthers open. When they have 

 shed their pollen, the other five do the same. During 

 this period the pistil is concealed in the tube, but 

 after the anthers have ripened and shed most of their 

 pollen, it also emerges and the two long stigmas 

 expand themselves. These two stages have been 

 already referred to (see Figs. 30 and 31). Under 

 these circumstances the butterflies can hardly fail to 

 carry the pollen from the anthers of young flowers 

 to the stigmas of older ones. Flies also visit this 

 species to feed on the pollen, and though they cannot 

 obtain any nourishment from flowers in the latter 

 condition, still they sometimes come to them, appa- 

 rently by mistake, and, must therefore occasionally 

 fertilise them. This species appears to have lost the 

 power of self- fertilisation. 



I have already referred to Lychnis vespertina and 

 L. diiirna in the first chapter. L. GitJiago, like 

 Dianthus, is adapted to butterflies. It agrees with 

 the flowers of that genus in the narrowness of the 



