i88 ANGIOSPERMAE DICOTYLEDON ES 



England, 3 bees i. Andrena cingulata F. (S., Sm.); 2. A. parvula K. (Sm.); 3. A. 

 minutula K. (S.). 



2112. V. officinalis L. (Herm. Miiller, ' Fertilisation/ p. 441, 'Alpenblumen,' 

 p. 272 ; Kirchner, ^ Flora v. Stuttgart,' p. 587 ; Knuth, 'Bl. u. Insekt. a. d. nordfr. 

 Ins.,' pp. Ill, 164; Loew, 'Bliitenbiol. Floristik/ pp. 391, 399.) Harm. Miiller 

 gives the following account of this species for Westphalia. The pale-blue flowers are 

 traversed by darker veins. They do not open so widely in the sun as those of 

 V. Chamaedrys. Some flowers are homogamous, others dichogamous. In the 

 former the two stamens are very thin at the base, and project obliquely from the 

 flower at some distance from the underlying style. Nectar is secreted as in the last 

 species, and insect visitors touch the stigma or anthers with various parts of their 

 bodies, effecting self- and cross-pollination indiscriminately. Should insect-visits fail, 

 the filaments twist inwards and downwards as the flowers begin to wither, this being 

 rendered possible by their attenuated bases, until the anthers touch each other and 

 the stigma, thus effecting autogamy. 



Stapley observed protandrous flowers in England. When these open the stigma 

 is above the anthers, so that automatic self-pollination is excluded. 



Kirchner noticed markedly protogynous flowers at Stuttgart, the style with its 

 mature stigma projecting for about 2 mm. from the still closed corolla. After this 

 expands the anthers do not dehisce for some time, and they are situated above the stigma 

 as in homogamous flowers. Warnstorf states that the flowers are also protogynous 

 at Ruppin, and the style with its mature stigma projects several millimetres from the 

 corolla before they open. He describes the pollen-grains as white in colour, ellip- 

 soidal, with thickened poles, densely beset with small tubercles, up to 50 /i long and 

 25 /u, broad. 



Visitors. The following were recorded by the observers, and for the localities 

 stated. 



Knuth (Schleswig-Holstein), the hover-fly Syritta pipiens Z., skg. ; (Thuringia), 

 the Empid Empis truncata Mg.^ skg. and effecting pollination (Bliitenbiol. Beob. in 

 Thiiringen,' p. 32). Herm. Miiller (Westphalia), an Empid (Empis livida Z., freq., 

 skg.), two hover-flies (Helophilus floreus Z., skg., and Syritta pipiens Z., do.), a small 

 bee (Halictus albipes F., po-cltg.), and 2 parasitic humble-bees Psithyrus vestalis 

 Fourcr 5, skg., and P. barbutellus K. 5, only skg. for a short time : (Alps), the humble- 

 bee Bombus mendax Gerst. 5, skg. Loew (Brandenburg), the Bombyliid Bombyliu5 

 minor Z., skg., and the Conopid Dalmannia punctata F., do. (' Beitrage,* p. 42): 

 (Switzerland), the hover-fly Syrphus luniger Mg. (op. cit., p. 61). MacLeod (Flanders) 

 4 short-tongued bees, 2 Syrphids, 3 Muscids, and 3 Empids (Bot. Jaarb. Dodonaea 

 Ghent, v, 1893, P- 347)- Scott-Elliot (Dumfriesshire), a humble-bee ('Flora 

 Dumfriesshire,' p. 129). 



2113. V. montana L. (Herm. MuUer, 'Alpenblumen,' p. 272, 'Weit. Beob. 

 Ill, pp. 32-3; Kirchner, 'Flora v. Stuttgart,' pp. 587-8.) The flower mechanisn 

 of this species agrees with that of V. Chamaedrys, but the flowers and inflorescence 

 are larger and more conspicuous, so that insect visitors are more numerous. 



Visitors. Herm. Miiller saw the honey-bee and a Sphegid (Ammophila sp.) i 

 the Alps, and in the course of two days he and his son observed the following i 

 Westphalia. 



J 



