226 



A NGIOSPERMAEDICOTYLEDONES 



Size of flowers, possibility of automatic self-pollination, formation of nectary, 

 and secretion of nectar, as in Forms IV and V. 

 (i) Corolla and style grow equally during anthesis, or the style a little less than 



the corolla. (Form VI.) 

 (2) The style elongates slightly more than the corolla during anthesis, so that] 



towards the end of this the stigma protrudes. (Form VII.) 

 Schulz says that Form I agrees with Miiller's first form completely, and Form VII | 

 more or less with his second. 



All forms agree as regards the remaining mechanism of the flower. The white ' 

 or pale-blue corolla is marked with violet streaks converging to the yellow-spotted 

 flower-base, and serving as nectar-guides. The upper lip forms an arched roof, 

 sheltering anthers and nectar from rain, and preventing the bee visitors from inserting 

 their proboscis above the anthers. The lower lobes of the upper anthers are united 

 with the upper lobes of the lower anthers, and the two upper ones are bound firmly 

 together. Hermann Miiller states, and Kirchner agrees with him, that the upper lobe 



Fig. 318. Euphrasia officinalis, L. (after Herm. Mttller). (i) Flower of the 

 sraall-flowered form, seen from the front (x 7). (2) The two right stamens, seen 



from the outer side. (3) Inner side of do., more strongly magnified. (4) Just 

 opened flower of the large-flowered form. a, stigma ; b, upper half of an upper 

 anther; c, lower half of do., united with the upper half of a lower anther; rf, lower half 

 of a lower anther ; e, style. 



of each anther has no point, but the lower one possesses a sharp, stiff spine, and the 

 two lower spines are certainly considerably longer than the upper ones. They 

 project downwards at the entrance of the flower, so that they are struck by bee 

 visitors. Schulz found, in the numerous flowers he investigated, that both lobes of 

 the upper anthers, as well as the upper lobes of the lower ones, always have a short 

 point, and the lower lobes of the latter a much longer one. The smooth and narrow 

 filaments lie close to the sides of the corolla, so that insect visitors can push their 

 heads into the entrance of the flower. In doing so they touch the anther-processes, 

 causing pollen to fall out of the anthers on to the heads of the insects, since lateral 

 dispersal is prevented by the hairs on the upper anthers. Kerner says that in the 



