544 



ANGIOSPERMAE DICOTYLEDON ES 



MacLeod (Pyrenees) observed a variety of this species (possibly G. Lapeyrou- 

 sianum) to be visited by a beetle, 3 Muscids, and 3 Syrphids. He describes it as 

 belonging to flower class C, while the other species of Galium belong to E. 



1247. G. verum L.xG. Mollugo L. (=G. ochroleucum Wolf.). (Knuth, 

 ' Weit. Beob. ii. Bl. u. Insekt. a. d. nordfr. Ins.,' p. 235.) In the island of Sylt 

 ( 2 - 7- '93) I nave seen numerous insects visiting in succession the flowers of 

 G. verum L. and G. Mollugo Z., and bringing about an interchange of pollen. 

 G. ochroleucum Wolf., which grows along with these two species, proves that this 

 crossing is effective, for it is a hybrid between them. 



Visitors. I observed the following Diptera, skg. 



1. Coenosia tigrina F.\ 2. Dolichopus aeneus Deg. ; 3. Hylemyia sp. $. 

 4. H. variata F. ; 5. Spilogaster communis R.-D.; 6. S. duplaris Zett. ; 7. S. 

 duplicata Mg. ; 8. Stomoxys stimulans Mg. 5. 



1248. G. verum L. (Herm. Mailer, 'Fertilisation,' p. 301, 'Weit, Beob.' Ill, 

 p. 70; MacLeod, Bot. Jaarb. Dodonaea, Ghent, v, 1893, p. 387; Knuth, 'Bl. u. 



Insekt. a. d. nordfr. Ins.,' pp. 82-3, 'Blii- 

 tenbiol. Beob. a. d. Ins. Riigen,' 'Weit. 

 Beob. ii. Bl. u. Insekt. a. d. nordfr. Ins.,' 

 p. 235; Schulz, 'Beitrage,' I, p. 67.) 

 The plants of this species that I examined 

 in the island of Rom possessed the fol- 

 lowing flower mechanism. The buds are 

 odourless, but when the corolla expands 

 a very strong smell of cumarin is exhaled. 

 (Kerner compares it to that of honey. 

 The flowers are only 4 mm. in diameter, 

 but being crowded into dense inflorescence 

 their intense yellow colour makes thei 

 conspicuous from a distance. They 

 markedly protandrous. In the first staj 

 of anthesis the four stamens bend back 

 far that the lower parts of their filament 

 lie between the lobes of the flat expande 

 corolla. At the same time the upr. 

 parts of the filaments are curved upwards, so that the dehisced anthers are in the 

 way of chance visitors. After these have completely or partly shed their polle 

 the two styles, so far united, separate, grow a little, and raise the mature stigma 

 almost to the level occupied by the anthers during the first stage of anthesis. 



Autogamy occasionally results from the bending over of the filaments, till the 

 anthers touch the stigmas. Automatic geitonogamy is frequently brought about by the 

 fall of pollen from a higher flower on to the stigmas of a lower one. Lastly, 

 inflorescences are so crowded, and different stocks grow so close together, ths 

 xenogamy may possibly be effected by the wind. Hermann Miiller describes 

 a remarkable difference in the size of flowers from different plants, and indicate 

 this in his illustration. (C/. Fig. 183.) I have not noticed this in R6m, nor 



Fig. 182. Galium sylvestrt, Pollick (after 

 Herm. Mttller). A. Young flower (x 7). B. 

 Pistil and nectary of the same (x 16). C. Older 

 flower ( X 7). D. Pistil and nectary of the same 

 (X 16). , nectary ; ov, ovary ; si, stigma. 



