Ii6 ANGIOSPERMAE—DICOTYLEDONES 



of the two outer nectaries, touch two of the adjacent anthers with their head or 

 proboscis, while those trj'ing to get at one of the two inner drops of nectar, only 

 come into contact with one anther. In either case they touch the stigma with the 

 other side of their head or proboscis. They may therefore effect either cross- or 

 self-pollination. Failing insect-visits, the long stamens effect automatic self-pollination. 

 Visitors. — Hermann Muller observed the following at Lippstadt. — 



A. Coleoptera. (a) Chrysomelidae: i. Cassida nebulosa Z. ; 2. Aphthona 

 nemorum Z., skg. ; 3. Chaetocnema concinna Marsh., skg. (V) Curculionidae : 4. 

 Ceutorhynchidius pumilio GylL, skg. (<:) Elateridae : 5. Limonius parvulus Pz. {d) 

 Hydrophilidae : 6. Paracercyon analis ]Pk. B. Diptera. {a) Bibionidae: 7. Bibio 

 laniger Mg., skg. (V) Empidae : 8. Empis sp., skg. (c) Muscidae : 9. Onesia floralis 

 R.-D., po-dvg. ; 10. Sarcophaga carnaria Z. 5 ; 11. Themyra putris Z., skg. (</) 

 Syrphidae: 12. Ascia podagrica F., po-dvg.; 13, Melithreptus sp., po-dvg. C. 

 Hymenoptera. Apidae : 1 4. Halictus flavipes F. 5, skg. and po-cltg. ; 1 5. H. luci- 

 dulus Schenck 5, ditto; 16. H. mono F. }, ditto; 17. H. nitidiusculus K. 5, ditto; 

 18. H. sexstrigatus Schenck 5, ditto ; 19. H. smeathmanellus K. 5, ditto ; 20. Sphecodes 

 ephippus Z., skg. 



In the island of Fbhr I saw Muscidae ; while MacLeod in Flanders noticed 

 2 Dipterids (Bot. Jaarb. Dodonea, Ghent, vi, 1894, p. 211). 



In Dumfriesshire (Scott-Elliot, 'Flora of Dumfriesshire,' p- 17) small flies have 

 been recorded. 



86. Iberis L. 



White to lilac homogamous flowers, with half-concealed nectar. 



287. I. amara L, (=1. Forestieri /or(f.) and 288. 1, mnbellata L. — The outer 

 petals of the marginal flowers are twice as large as the inner ones (Kerner). 



Visitors of I. amara (=1. Forestieri /bra'.). — MacLeod noticed a Muscid in the 

 Pyrenees. Alfken observed the following Apidae, skg., at Bremen. — 



I. Andrena albicans Mull. S; 2. A. albicrus K.i; 3. A. praecox Scop. $; 4. 

 Bombus lapidarius Z. 5 ; 5. B. lucorum Z. 5 ; 6. B. terrester Z. j ; 7. Osmia rufa Z. S. 



289. I. pinnata L. — Hildebrand states that this species is almost self-sterile 

 (Ber. d. bot. Ges., Berlin, xiv, 1896). 



290. I. saxatilis L. — According to Briquet {'jfitudes d. biol. flor. d. les Alpes 

 Occident.') the sepals are spreading and the corolla white and zygomorphous. The 

 diameter of the corollas of the outer flowers of each inflorescence is about 5 mm., and 

 the inner flowers are only about half as large. The stigma is beneath the introrse 

 anthers of the four long stamens, but as these turn outwards, while those of the two 

 short ones dehisce laterally, insect agency is necessary for pollination, although the 

 flowers are homogamous. After fertilization the filaments and style assume a dark 

 violet colour (according to Kirchner). 



Visitors. — Cross- and self-pollination are brought about by flies, wasps, bees, 

 and Lepidoptera. 



87. Biscutella L. 



Yellow homogamous flowers, with half-concealed nectar. Four nectaries, of 

 which, however, only two are functional. 



