45° ANGIOSPERMAE—MONOCOTYLEDONES 



three comers of the ovary. There are six entrances to this at the base of the style, 

 one between every pair of stamens. These entrances to the nectar are so narrow 

 that MacLeod is inclined to put the flowers into class L. They are feebly 

 protogynous. At first the perianth lobes are close together, so that only the 

 stigma is touched by visitors. They soon diverge, however, and the anthers 

 dehisce after the filaments have bent widely outwards. As the stigma projects 

 about 4 mm. beyond the anthers, self-pollination is no doubt excluded. 



Visitors. — MacLeod (Pyrenees) only observed 2 flies, and did not see the 

 normal visitors (Lepidoptera). 



2742. A. fistulosus L. (Knuth, ' Bliitenbiol. Beob. a. d. Ins. Capri.')— The 

 flowers of this species are very little visited by insects on the island of Capri, as 

 the many-flowered, branching inflorescences always set but few fruits. Automatic 

 self-pollination is therefore impossible or ineffective. 



883. Asphodeline Reichb. 



2743. A. lutea Reichenb. (=Asphodelus luteus L.). (Francke, Inaug.-Diss., 

 Halle, 1883.) — Francke says that the flowers of this species are protogynous for 

 some hours, and then homogamous. 



884. Omithogalum L. 



Literature. — Kirchner,' Flora v. Stuttgart,' p. 58; Grassmann, 'Die Septaldriisen.' 



Flowers pale yellow-green in colour, or white inside and mostly green outside, 



with half-concealed nectar secreted by three septal glands in the ovary. These 



contract above and form a narrow passage leading outwards, through which the 



secretion exudes and trickles down the furrows of the ovary. Sometimes gynodioecism. 



2744. O. umbellatum L. (Kerner, 'Nat. Hist. PI.,' Eng. Ed. i, II, p. 311 ; 

 Kirchner, 'Flora v. Stuttgart/ p. 59; MacLeod, BoL Jaarb. Dodonaea, Ghent, iv, 

 1892; Warnstorf, Schr. natw. Ver., Wemigerode, xi, 1896.) — In flowers of this 

 species the perianth leaves are milk-white inside and green outside, with a narrow 

 white margin. In sunny weather they expand to a star 30-45 mm. in diameter. 

 They are protogynous, but the stigma is still receptive when the anthers dehisce. 

 Kirchner states that of the six stamens the anthers of the three outer ones dehisce 

 first, and then those of the three inner ones. At first all the stamens are stretched straight 

 out; after dehiscence the upper halves of the filaments bend gradually outwards, 

 while the lower halves remain apposed to the ovary. In this way six narrow canals 

 are formed, of which the three apposed to the septal glands contain nectar. The 

 flowers close after midday and in dull weather, so that automatic self-pollination 

 now takes place in older flowers by contact of anthers and stigmas. According 

 to Kerner's description, on the contrary, the anthers of the three inner, longer 

 stamens dehisce a day earlier than those of the outer, shorter ones, and I can 

 confirm this from plants in the garden of the Oberrealschule in Kiel. Insect- 

 visits are necessary for pollination at first, in consequence of the 2 mm. distance 

 between anthers and stigma; towards the end of anthesis the stamens bend so 

 far inwards that anthers and stigma come into contact, and automatic self-pollination 

 takes place. Kirchner observed stocks bearing flowers in which the anthers always 

 remained closed, these being therefore functionally female. Warnstorf describes the 



