SELAGINEAE 241 



exserted from the corolla-tube, nectar-sucking Lepidoptera must brush stigma and 

 anthers with their proboscis or head, thus bringing about cross-pollination. This 

 can also be effected by pollen-collecting bees or pollen-devouring flies, but only 

 Lepidoptera succeed in reaching the nectar. 



aaio. G. vulgaris L. (Herm. Miiller, ' Alpenblumen,' pp. 327-8.) — This 

 species is protandrous, and if visited by insects the pollen is removed before the 

 stigma matures, thus rendering cross-pollination inevitable. Should such visits fail, 

 automatic self-pollination is easily effected, pollen falling from higher flowers on to 

 the stigmas of lower ones. 



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

 stated. — 



Herm. Miiller, a Lepidopterid, 2 bees, and the beetle Meligethes. Schletterer 

 and von Dalla Torre (Tyrol), the bee Prosopis hyalinata Sm. 



2211. G. cordifolia L. (Ricca, Atti Soc. ital. sc. nat., Milano, xiii, 1870 ; 

 Herm. Miiller, 'Alpenblumen,' p. 328; Kemer, 'Nat. Hist. PI.,' Eng. Ed. i, II, 

 pp. 91-2, 123-4.) — The flowers of this species are protogynous with a persistent 

 stigma. The style with mature stigma projects (while the flower is still young) 

 beyond the unripe anthers. When the latter dehisce, the filaments elongate to such 

 an extent that they equal, or even exceed the style in length. Hence cross-pollina- 

 tion by insect-visits is ensured during the first stage of anthesis, while in the second 

 self-pollination is possible. Kemer says that the anthers close up in damp weather, 

 thus protecting the pollen from wet. 



Visitors. — Herm. Miiller observed 5 Lepidoptera, 2 bees, and a fly. 



2212. G. nudicaulis L. (Herm. Miiller, 'Alpenblumen,' pp. 328-9.) — This 

 species is protogynous with a persistent stigma, and agrees in all other respects with 

 G. vulgaris. 



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

 stated. — 



Herm. Miiller (Alps), 4 Lepidoptera, a small bee, and a hover-fly. MacLeod 

 (Pyrenees), 2 bees (Halictus sp.), 2 Lepidoptera, a hover-fly, and 2 Muscids (Bot. 

 Jaarb. Dodonaea, Ghent, iii, 1891, p. 323). 



LXXXI. ORDER VERBENACEAE JUSS. 



The only genus of this order found in Central and South Europe, and in North 

 America, is — 



696. Verbena L. 



Homogamous bee flowers ; with nectar secreted by the base of the ovary and 

 stored at the bottom of the short corolla-tube. Protection against unbidden guests 

 is afforded by a ring of hairs which firmly closes up the corolla-tube. 



2213. V. officinalis L. (Sprengel, 'Entd. Geh.,' p. 57; Herm. Miiller, 

 ' Weit. Beob.,' Ill, pp. 42-4, 'Alpenblumen,' p. 307; MacLeod, Bot. Jaarb. 

 Dodonaea, Ghent, v, 1893, pp. 362-3; Kirchner, 'Flora v. Stuttgart,' p. 645; 

 Knuth, ' Bliitenbiol. Herbstbeob.') — The small, pale-violet flowers of this species are 

 aggregated in long, loose paniculate spikes. The corolla-tube is 3-4 mm. long ; its 



