62 ANGIOSPERMAE—DICOTYLEDONES 



with a strong tendency to autogamy, for both kinds of sexual organ mature in 

 the bud, and the stamens bend toward the stigmas when the flower opens. The 

 latter are 4-7 in number in Greenland (Abromeit, ' Bot. Ergeb. v. Drygalski's 

 Gronlands exped.,' p. 29). 



Visitors. — In Nova Zemlia flies were observed by Ekstam, who also noticed 

 a small po-dvg. fly on the flowers in Spitzbergen, at a height of 1000' above the 

 sea-level. 



Alfken saw at Brerr.en the following pollen-collecting Apidae on garden 

 plants. — 



I. Andrena albicans Miill. 5; 2. A. nigro-aenea K.^; 3. A. nitida Fourcr. 5; 

 4. A. parvula K. ^; 5. Osmia rufa L. 5. All po-cltg. 



133. P. Rhoeas L. (Heim. MuUer, 'Fertilisation,' 93-4, ' Weit. Beob.,' I, 323 ; 

 Hoffmann, 'Bot. Ztg.,' Leipzig, xxxvi, 1878, p. 290; Beyer, 'D. spont. Bewegungen 

 d. Staubgefasse u. Stempel' ; Kirchner, 'Flora v. Stuttgart,' p. 277 ; Knuth, 'Bl. u. 

 Insekt. a. d. nordfr. Ins.,' pp. 22, 148.) — The petals are scarlet, with a black patch 

 at the base. Even in the bud the numerous stamens are mature, so that the pollen- 

 covered anthers come into coniact with the lower parts of the flattened but already 

 mature stigmas, and dust them with pollen. Hoffmann states, however, that this 

 inevitable automatic self-pollination is ineffective. After the flowers have opened 

 either cross- or self-pollination may be brought about by insect-visits. Warnstorf 

 (Verb. bot. Ver., Berlin, xxxvii, 1895) describes the pollen-grains as grey-green, and 

 spherical or almost spherical when examined in water, very finely granular, with 

 an average of 37-5 yu.. 



Visitors. — Hermann Miiller (H. H.) in Westphalia, and myself (Kn.) in 

 Schleswig-Holstein, have observed the following. — 



A. Coleoptera. {a) NiiiduUdae -. i. Meligethes, very freq., po-dvg. (H. M.); 

 (3) Oedemeridae : 2. Oedemera virescens Z., po-dvg. (H. M., Thuringia). (c) Scara- 

 haeidae: 3. Oxythyrea funesta /'oo'a, very freq., dvg. the flowers (H. M.). B. Diptera. 

 (a) Empidae : 4. Empis livida L. (H. M.). (fi) Muscidae : 5. Ulidia erypthrophthalma 

 Mg. (H. M., Thuringia). {c) Syrphidae: 6. Cheilosia, po-dvg. (H. M.); 7. Syrphus 

 ribesii Z., po-dvg. (Kn.) ; 8. S. umbellatarum F., po-dvg. (Kn.). C. Hymenoptera. 

 Apidae : 9. Andrena dorsata K. 5, freq., po-cltg. (H. M.) ; 10. A. fulvicrus K. 5, freq., 

 po-cltg. (H. M.) ; II. Apis mellifica Z. 5 (Kn.); 12. Bombus terrester Z. (Kn.) ; 13. 

 B. lapidarius Z. 5, and 14. Halictus cylindricus K. 9; all po-cltg. (H. M.) ; 15. H. 

 flavipes F. 5, freq., po-cltg. (H. M.) ; 1 6. H. leucopus K. 5, po-cltg. (H. M., Thuringia) ; 

 17. H. longulus Sm. 5, po-cltg. (H. M.) : 18. H. maculatus Sm. 5 (H. M.) ; 19. H. 

 sexnotatus K. 5, very freq., po-cltg. (H. M.); 20. H. smeathmanellus K. 5, po-cltg. 

 (H.M., Thuringia). D. Orthoptera. 21. Forficula auricularia Z. (H. M.). Friese 

 noted — in Mecklenburg — Osmia papaveris Z/r., occasional ; Schletterer — at Pola — 

 Eucera longicornis, Z.; MacLeod — in the Pyrenees — Bombus terrester, Z. 5, po- 

 cltg., also — in Flanders — 3 hover-flies (Bot. Jaarb. Dodonaea, Ghent, vi, 1894, 

 pp. 184-5). 



134. P. Argemone L. (Herm. Muller, ' Fertflisation,' p. 94; MacLeod, Bot. 

 Jaarb. Dodonaea, Ghent, vi, 1894, pp. 185-6 ; Knuth, 'Bl. u. Insekt. a. d. nordfr. Ins.,' 

 pp. 22, 148; Warnstorf, Verb. bot. Ver., Berlin, xxxviii, 1896.) — The red petals are 

 blotched with black at their bases. The flowers agree in structure with those of 

 the last species, except that the anthers come into contact with a smaller part 

 of the stigmas. Warnstorf describes them as pseudo-cleistogamous, because the 



