72 ANGIOSPERMAE—DICOTYLEDONES 



and if it has come from another flower of the same species effects cross-pollination. 

 This plant — according to Hildebrand's experiments — is self-fertile. Kerner confirms 

 the fact of autogamy in the absence of insect-visits. 



159. C. lutea DC. (Hildebrand, op. cit. ; Herm. Miiller, 'Fertilisation,' p. 99, 

 ' Weit. Ikob.,' I, p. 324.) — The flower mechanism essentially agrees with that of 

 the last species. 



VisnoRS. — Herm. Miiller — at Lippstadt — observed Bombus agrorum F. 5, skg. 

 legitimately, and he also saw the following bees at Jena.- — 



I. Anthophora aestivalis Pz. 5 and S, skg. ; 2. Bombus confusus Schenck 5, skg. ; 

 3. B. lapidarius L. 5, skg. ; 4. B. pomorum Pz. 5, skg. ; 5. B. rajellus K. 5, skg. ; 

 (■>. Eucera longicornis L. ^, skg. ; 7. Haliclus xanthopus K. 5, skg., or at least 

 attempting to do so ; 8. Osmia aurulenta Pz. j, skg. ; 9. Psithyrus rupestris F. 5, skg. 



Sch'enck — in Nassau — observed the following bees skg.: — Osmia cornuta Ltr.., 

 and Podalirius acervorum L. In Dumfriesshire (Scott-Elliot, ' Flora of Dumfries- 

 shire,' p. 10) a humble-bee was noticed. 



160. C. acaulis Pers. — Kerner states that the flower mechanism of this plant 

 resembles that of the last species. 



161. C. bracteata Pers., and 162. C. kolpakowskiana Kegel. — 

 Visitors. — Loew observed — in the Berlin Botanic Garden — Anthophora pilipes 



F. ?, skg. 



163. C. claviculata DC. (Knuth, Bot. Centralbl., Cassel, lii, 1892, pp. 1-2; 

 Hart, Nature, London, x, 1874, p. 5.) — The inconspicuous whitish flowers are only 

 6-8 mm. long and 2 mm. broad, and are arranged in racemes with few (at most six) 

 flowers. They are homogamous. The stamens are at first rather shorter than the 

 style, so that self-pollination can only occur when the pollen is discharged into 

 the dark hlac hood which ensheaths the stigma. The hood when pressed down 

 does not return to its original position : the stigma remains concealed under the 

 folded plate of the inner upper petal. The smallness of the flower makes an 

 exact study of its mechanism difficult. 



Visitors. — I have not observed any, but have seen traces of the activity of 

 nectar-sucking insects. In many flowers the connection between the spurred petal 

 and the three others had been forcibly severed, so that these latter must have formed 

 a convenient platform for bees. Willis (' Fls. and Ins. in Gt. Britain,' Part i) noticed 

 the following near the south coast of Scotland. — 



Hymenoptera. Apidae: i. Bombus agrorum F.^ freq., skg. ; 2. B. terrester Z., 

 skg. ; both effecting pollination. Every flower appears to set fruit. 



In Dumfriesshire (Scott-Elliot, 'Flora of Dumfriesshire,' p. 10) there have been 

 observed, — Apis, 4 humble-bees, a short-tongued bee, and a Muscid. 



48. Fumaria L. 



Homogamous bee flowers. The nectar is secreted by a short process from the 

 upper filament. It is concealed in a short rounded pouch of the upper petals. The 

 other arrangements are as in Corydalis. 



164. F. officinalis L. (Hildebrand, op. cit., p. 450; Herm. Miiller, 'Ferti- 

 lisation,' pp. 99-100; MacLeod, Bot. Jaarb. Dodonaea, Ghent, v, 1893, pp. 188-90; 



