RUBIACEAE 545 



any of the North Frisian Islands, where the plant grows in enormous numbers 

 on the dunes. Schulz, however, observed considerable variations as to the size 

 of flowers at Halle and in Thuringia, the extreme forms being connected by 

 a large series of intermediate stages. He further remarked variations between 

 strong protandry and complete homogamy. In the latter case automatic self- 

 pollination is possible; but is prevented at a later stage by the stamens bending 

 quite out of the flowers. 



Visitors. — Hermann MuUer gives the following list (T.= Thuringia; 0.= 

 Bavarian Oberfals). — 



A. Coleoptera. {a) Cerambycidae : i. Strangalia bifasciata Mull., dvg. the 

 anthers (T.). {b) Elateridae: 2. Agriotes gallicus Lac. (T.). (c) Mordellidae : 

 3. Mordella aculeata Z. (T.) ; 4. M. fasciata F. (T.). {d) Oedemeridae: 5. Oedemera 

 podagrariae Z., po-dvg. (T.). (e) Scarabaeidae: 6. Cetonia aurata Z., dvg. the 

 flowers (T.). B. Diptera. (a) Bombyliidae : 7. Anthrax flava Mg., nect-lkg. (O.). 



Fig. 183. Galium verum, L, (after Herm. Miiller). (i) Youngf flower, from a plant with very small 

 blossoms. The anthers are covered with pollen, and the stigmas are immature (X 7). (2) Older flower 



of the same plant with faded anthers, curved out of the corolla, and mature stigmas. (3) Flower of 

 a plant with large blossoms, in the middle of anthesis ; older than i, younger than 2 ( x 7). (4) Ditto, 

 seen from the side. 



(3) Conopidae : 8. Conops flavipes Z., nect-lkg. (c) Muscidae : 9. Ulidia erythro- 

 phthalma Mg. freq., nect-lkg. (T.). ((f) Syrphidae: 10. Eristalis arbustorum Z., 

 po-dvg. (T.). C. Hymenoptera. (a) Apidae: 11. Halictus cylindricus F. S, 

 nect-lkg. (O.) ; 12. Prosopis sp. S, nect-lkg. (O.). {b) Chrysididae : 13. Holopyga 

 ovata Dahlb., nect-lkg. (T.). (c) Tenthredinidae : 14. Pachyprotasis rapae K., 

 nect-lkg. D. Lepidoptera. Sphingidae: 15. Macroglossa stellatarum Z., vainly 

 searching for nectar (T.); 16. Zygaena lonicerae Esp. {T.). 



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



Knuth (Sylt and Fohr), numerous skg. Diptera. — i. Coenosia tigrina F.; 

 2. Dolichopus aeneus Deg.; 3. Hylemyia sp. ; 4. H. variata F.; 5. Musca sp. ; 

 6. Spilogaster communis R.-D.; 7. S. duplaris Zetl.; 8. S. duplicata Mg.; 

 9. Stomoxys stimulans Mg.; the hover-fly Syritta pipiens Z., po-dvg., and the 

 butterfly Epinephele janira Z., trying to suck : (Rugen), the beetle Strangalia 

 melanura Z., po-dvg., and the hover-fly Syritta pipiens Z., do. : (Helgoland), 

 Muscids, all skg. — i. Coelopa frigida Fall.; 2. Lucilia caesar Z. ; 3. Scatophaga 

 stercoraria Z. ; 4. small undetermined sp. (Bot. Jaarb. Dodonaea, Ghent, viii, 1896, 

 p. 34). Alfken (Bremen), the Chrysomelid Agelastica halensis Z., freq. MacLeod 

 (Pyrenees), 2 Muscids (op. cit., iii, 1891, p. 345). Scott-Elliott (Dumfriesshire), 

 2 hover-flies and 4 Muscids (' Flora of Dumfriesshire,' p. 85). 



1249. G. boreale L. (Axell, ' Om Anord. for Fanerog. vaxt. Befrukt.,' p. 97 ; 

 Herm. Miiller, ' Fertilisation,' pp. 301-2, 'Weit. Beob.,' IH, p. 70, ' Alpenblumen,' 

 p. 390; Schulz, 'Beitrage,' I, pp. 66-7.) — This species agrees with G. sylvestre as 

 regards secretion of nectar, its slight protandry, and the relative positions of stamens 

 and pistil. It follows that crossing is likely to be eS'ected by insect -visits; falling 



