RANUNCULACEAE 5 



2. Atragene L. 



Homogamous bee flowers. The large sepals serve for attraction; the small 

 petals are converted into nectaries. 



7. A. alpina L. ( = Clematis alpina Miller). (Herm. Miiller, ' Alpenblumen,' 

 pp. 124-5; Ricca, 'Oss. suUa fecondaz. incroc. d. veget. alp. e subalp.'; Kerner, 

 'Nat. Hist. PI.,' Eng. Ed. i,II, pp. 349-50; Schulz, ' Beitrage,' p. i.) — A characteristic 

 bee flower. According to Hermann Miiller, this plant is homogamous in the Alps, 

 but self-pollination is quite excluded, so that fertilization is entirely due to visitors, 

 which are chiefly Apidae (see Fig. 2). 



Fig. 2. Airagene alpina^ L, (after Hermann Miiller). A. Flower seen from the side(x '\). B. The 

 same after removal of a sepal. C. One of the four large petals. D. One of the innermost small petals, 

 with a small anther-lobe on one side at the end. E. A stamen seen from the side. F. The same seen 

 obliquely from within. G. A carpel. 



According to Kerner the flower mechanism of Atragene alpina completely 

 agrees with that of Clematis integrifolia, self-pollination of old flowers being brought 

 about automatically by elongation of the carpels. 



Visitors. — Herm. Miiller observed one bee (Eucera) and one beetle; Ricca 

 observed humble-bees ; Schulz noticed Apidae more particularly. 



3. Thalictrum L. 



Pollen flowers in which the stamens serve for attraction, or anemophilous 

 flowers occasionally visited by insects. Kerner observed opening and closing of 

 the anthers as a result of variations in the humidity of the air. 



8. T. aquilegifolium L. (Herm. Miiller, ' Fertilisation,' p. 70, ' Alpenblumen,' 

 p. 115; Beyer, ' D. spont. Bewegungen d. Staubgefasse u. Stempel ' ; Ricca, ' Oss. 

 suUa fecondaz. incroc. d. veget. alp. e subalp.' ; Schulz, ' Beitrage,' II, pp. 1-2 ; 

 Kerner, 'Nat. Hist. PI.,' Eng. Ed. i, II; Knuth, ' Bloemenbiol. Bijdragen.') — This 

 tall plant is conspicuous from a distance, owing to the many stiff club-shaped 

 stamens of pale violet colour, which radiate from the centre of the numerous 



