AMARYLLIDEAE 



433 



long-tongued crepuscular and nocturnal Lepidoptera and the bee Anthophora pilipes 

 occur as visitors (at Florence). 



864. Leucojum L. 



White flowers, marked with green spots below the tip of the perianth leaves, 

 apparently secreting no free nectar, but possessing a ridge of juicy tissue at the base 

 of the style. 



2699. L. vemum L. (Sprengel, 'Entd. Geh.,' pp. 18 1-2 ; Kerner, ' Nat. Hist. 

 Pl.,'Eng. Ed. I, II, pp. 170, 190, 201, 274; Knuth, ' Bloemenbiol. Bijdragen'; Bot. 

 Centralbl., Cassel, Ixxiv, 1898, pp. 161-5.) — The inner parts of flowers of this species 

 are protected from rain by the pendulous position and the roof-like arrangement 

 of the perianth whorls. Sprengel considered the middle part of the style the 

 nectar-secreting organ. He says : ' I have found nectar in this part in all flowers 

 except the very old ones. Though this use for the style 

 is very unusual, its form is equally so, and only to be 

 explained by this theory, being so thick, as is also the 

 green nectar-guide with which it is decorated at the tip.' 

 Kerner describes the fleshy base of the flower as the 

 nourishment offered to visitors. As all the petals are 

 longitudinally streaked, and the colourless streaks converge 

 to the base of the flower, this supposition, though I cannot 

 confirm it from direct observation, becomes still more 

 probable. Since the petals are also a little swollen at 

 their bases, and are situated on the margin of the swelling 

 into which the stamens are also inserted, it is not improb- 

 able that the whole tissue of the flower-base contains sap 

 and is bored by visitors. I was never able to recognize 

 secretion of free nectar. Regarding the probable position 

 of the nectary cf. L. aestivum. The younger flowers 

 have a rather strong odour of violets, the older an 

 unpleasant smell distantly resembling that of bitter almonds. 



The pendulous flowers are homogamous. The anther-lobes of the six stamens 

 dehisce downwards, and when lightly touched allow a small quantity of yellow 

 pollen to fall out, so that insect visitors must be dusted with it as soon as they enter 

 the flower. As the stigma projects slightly beyond the anthers it is touched first 

 by visitors, and is thus cross-pollinated. In widely opened flowers the anthers 

 are at first so far from the stigma that autogamy cannot take place. This, however, 

 occurs when the flowers close in the evening, the anthers and the usually pollen- 

 covered inner sides of the petals then coming into contact with the stigma. 



Visitors. — Knuth observed numerous skg. and po-cltg. honey-bees, and also 

 (21. 3/96) the butterfly Vanessa urticae L., skg. MacLeod (Flanders) also noticed 

 the honey-bee (Bot. Jaarb. Dodonaea, Ghent, v, 1893, P- S'S)- 



2700. L. aestivum L. (Loew, ' Bliitenbiol. Floristik,' p. 349 ; Knuth, 

 ' Bloemenbiol. Bijdragen,' Bot. Centralbl., Cassel, Ixxv, 1898.) — The flower mechanism 

 of this species is the same as that of the preceding one, but the style is considerably 



Fig. 392. Leucojum vertium, 

 L. (from nature). Partly dissected 

 flower, after removal of the peri- 

 anth and three stamens ( x 2). 

 a, anthers; b, spongy sugar- 

 containing base of the flower ; 

 fk, ovary with ovules ; s, stigma. 



DAVIS. Ill 



Ff 



