322 



BRITISH FLOWERING PLANTS 



of which, according to Mr. Frederick Townsend, occur in 

 Britain.^ No doubt the plants vary wonderfully in the 

 size and form of the leaves, in the size, colour, and 

 arrangement of the flowers, and if one district or country 

 is considered alone they may be divided into well-marked 

 forms. I have, however, examined the plant in France 

 and Switzerland as well as in England, and believe that 

 if we take a sufficiently large area, such as Western 

 Europe, intermediate forms can be found between all 

 the varieties, so that I cannot but accept, at any rate 

 provisionally, the view of the two great English 

 botanists whom I have quoted. 



E. officinalis. — H. Miiller distinguishes two principal 

 forms : one with large flowers adapted for cross-fertilisa- 

 tion, one with smaller ones for spontaneous self-fertilisa- 



FiG. 209. — Euphrasia officinalis. Fig. 210. — Euphrasia officinalis. Partial sec- 

 Shoot, with flower, pistil, and tion of flower, enlarged, a, anthers ; ca, 

 fruit ; enlarged. calyx, uncut ; co, corolla ; /, filaments of 



stamens ; s, stigma. 



tion. The upper lip (Fig. 210) protects the anthers 

 and nectar from rain. The ripe stigma projects from 

 the flower even before it opens. The corolla gradually 

 elongates so as eventually to reach the stigma, thus 

 bringing the anthers close to it. In this respect, how- 



' Monograph of the British species of Euphrasia, Journal of Botany, 1897. 

 See also Babington, Manual of British Botany, ed. ix., H. and J. Groves, 1904. 



