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ANGIOSPERMAEDICOTYLEDONES 



664. Veronica L. 



Flowers blue in colour, more rarely red or white; with concealed nectar 

 secreted by a disk below the ovary, and stored in the lower part of the short 

 corolla-tube. The larger blossoms are usually homogamous or dichogamous 

 hover-fly flowers, the stamens and style serving as an alighting-platform. Kerner 

 says that geitogamy takes place in species with a spicate inflorescence. S 



2in. V. Chamaedrys L. (Sprengel, 'Entd. Geh.,' p. 51; Herm. Muller, 

 'Fertilisation,' pp. 438-9, ' Alpenblumen/ p. 272, 'Weit. Beob.,' Ill, p. 31; 

 Kirchner, 'Flora v. Stuttgart,' pp. 586-7; Loew, ' Bliitenbiol. Floristik/ p. 391; 

 Knuth, 'Bl. u. Insekt. a. d. nordfr. Ins.,' pp. ni, 164, ' Bloemenbiol. Bijdragen.') 

 This species bears homogamous hover-fly flowers, arranged in tolerably conspicuous 

 racemes. The corolla is bright blue, decorated with darker lines and a lighter 

 centre. Nectar is secreted by a fleshy yellow hypogynous disk, and covered by 

 hairs lining the corolla-tube, these serving as a protection against rain. The style 



^Ky 



Fig. 293. Veronica Chamatdrys, L. (A after Henn. Mailer; B, C, ZJfrom nature). A. FIomi-ct 

 seen from the front. B. Do., with the stamens drawn together, as done by a hover-fly. C. E>o., with 

 a visitor (Asda podagrica), which has drawn the stamens under its abdomen. D. Pistil and nectar}- 

 (X 3). 



directed obliquely downwards, and the two stamens diverge laterally, automatic 

 self-pollination being therefore impossible, although stigma and anthers mature 

 simultaneously. The lower corolla-lobe is the most convenient alighting-platform, 

 so that when an insect settles it must first touch the stigma with its ventral siu^face. 

 The visitor then seizes the thin bases of the filaments, which are easily drawn 

 together, and its under-side is thus dusted afresh wth pollen. In further visits the 

 same procedure is repeated, so that crossing is eff"ected and fresh pollen taken up 

 each time. Even if a hover-fly settles on one of the lateral corolla-lobes the 

 under-side of its abdomen will sometimes be struck by one of the stamens. Kerner 

 finds that automatic self-pollination takes place in the closed flowers during bad 

 weather. He says that the flowers open about 9-10 a.m., closing again about 

 5-6 p.m. 



Visitors. Alfken observed the following at Bremen and Hanover. J 



A. Coleoptera. Byrrhidae : i. Cistela sericea Forst. B. Diptera. {a) Em 

 pidae: 2. Empis tessellata F., skg. (3) Syrphidae: 3. Ascia podagrica r., ver) 

 common, skg. ; 4. Syrphus balteatus Deg., skg. C. Hymenoptera. (a) Apidae 

 5. Andrena chrysopyga ScJunck $, occasional 6. A. cingulata F. % skg. and po-cltg. 



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