438 ANGIOSPERMAEMONOCOTYLEDONES 



Hist. PI.,' Eng. Ed. i, II, pp. 120, 203, 240, 379; Loew, 'Bliitenbiol. Floristik,' 

 pp. 353-4; Mattei, 'I tulipani di Bologna.') The fragrant yellow flowers of this 

 species are homogamous. Kerner says that they secrete nectar at the base of the 

 stamens, the outer side of each filament being provided with a pit, by which nectar is 

 secreted and stored. This pit is completely covered by a tuft of hairs, so that an 

 insect probing for nectar must raise the stamen. Kirchner also considers this spot 

 a nectary, and Mattei states that free nectar is found there. Loew has examined the 

 North German plants of this species, and observed no secretion of nectar at the base 

 of the stamens ^ He found that in bright sunshine the flowers expand to a star 

 about 8 cm. in diameter, and that the stamens also diverge almost at right angles 

 from the ovary. The filaments are provided with a tuft of hairs not only on the 

 hollowed lower side of their base, but also on their upper side; but no free nectar 

 could be discovered here. The yellow stigma, however, which is the highest part of 

 the flower, often secretes minute drops of liquid, and small bee visitors (species of 

 Andrena and Halictus) flew first to this, and afterwards to the anthers, which are 

 situated lower down and are less conspicuous, on account of their darker colouring, 

 to collect pollen. They thus eff'ected cross-pollination regularly. Loew never 

 observed such visitors searching for nectar at the base of the stamens, but they 

 sometimes probed at the base of the ovary. Besides these bees there were some- 

 times some flies also, which licked the small drops ofl" the stigma. 



Kerner says that should insect visits fail, autogamy may take place, the flower 

 stalk ultimately bending down so far that the stigma is brought into the line of fall 

 of the pollen. 



Visitors. Loew (' Blutenbiol. Beitrage,' II, pp. 72-3) observed small po-cltg. 

 bees (Andrena fulva Schr., A. extricata Sm., and Halictus sp.), and po-dvg. flies 

 (Eristalis numonim Z., Syrphus ribesii Z., Myopa testacea Z., and Anthomyia sp.). 



2708. T. Oculus-solis St. Amans. (Kirchner, ' Beitrage,' p. 5 ; Knuth, ' Bloe- 

 menbiol. Bijdragen.') Kirchner has described the flower mechanism of this South 

 German species in plants run wild from the Hohenheim Exotic Garden. They 

 bear homogamous pollen-flowers, devoid of nectar, and possessing a feeble fragrance 

 resembling that of Taraxacum. They are erect, with scarlet perianth leaves, glossy 

 at the base and marked with a large, black, yellow-edged spot ; the three petals also 

 possess a yellowish median streak. The filaments are glabrous, yellow at the base, 

 and blackish at the tip ; the anthers contain black pollen. The stigma is usually at 

 the same level as the tips of the anthers, but the latter not infrequently project about 

 5 mm. beyond it. Automatic self-pollination is excluded by the position of the 

 flowers, in addition to the fact that there is a distance of 5-8 mm. between stigma 

 and anthers. 



Visitors. Knuth (gardens in Kiel) observed the honey-bee, po-cltg. 



2709. T. Gesneriana L. (Van Tieghem, ' Recherches ' ; Knuth, op. cit.) 

 The feebly fragrant flowers of this species, rendered very conspicuous by the vivid 

 colouring of the perianth leaves, expand in sunshine like a star. They are homo- 

 gamous pollen-flowers, though Tieghem states that nectaries are indicated in the 



^ Cf. the foot-note to Leucojum aestivum Z. 



