130 ANGIOSPERMAEDICOTYLEDONES 



of the kind when it approaches a flower first touches the stigma and then separates 

 the united anthers, thus usually effecting crossing. Should insect-visits fail, automatic 

 self-pollination is now and then possible, owing to the close proximity of the anthers 

 and stigma just after the flowers open. Towards the end of anthesis, but not earlier 

 as a rule, the corolla falls off" and the stigma is drawn between the anthers so as to 

 effect autogamy. 



Visitors. Vide supra. Ducke and Graeffe observed the very long-tongued bee 

 Osmia macroglossa Gerst., as a frequent and exclusive visitor at Bozen. Schulz saw 

 a number of flowers perforated at the base by the humble-bee Bombus terrester L. 



1987. O. echioides L. (= O. Vaudense Gremit). (Briquet, 'tudes de biol. 

 flor. dans les Alpes Occident.') The flowers of this species are sulphur-yellow in 

 colour, smell like honey, and secrete abundant nectar from five little scales at the 

 base of the corolla. Briquet says they are visited by humble-bees, bees, and butter- 

 flies, which regularly effect cross-pollination. The horizontal corolla is 20-3 mm. in 

 diameter, and its entrance 5 mm. The long thin style projects 5 mm. from the 

 flower, and is surrounded by the anthers, which are laterally fused at their bases. 

 Kirchner states that, should insect-visits fail, automatic self-pollination can only be 

 brought about by fall of the corolla. 



Visitors. Vide supra. 



612. Cerinthe L. 



Homogamous bee and humble-bee flowers ; with nectar secreted by the swolk 

 fleshy base of the ovary, and sheltered in the uppermost part of the penduloi 

 bell-shaped corolla. 



Kerner states that the peduncle bends down in late anthesis, causing the flowe 

 to assume a nodding or pendulous position, and bringing the stigma into the line 

 fall of the pollen, so that autogamy is inevitable. 



1988. C. alpina Kit. (=C. glabra Mill.). (Herm. Mtiller, ' AlpenblumenJ 

 pp. 264-6.) The pendulous flowers of this species are pollinated by humble- 

 with a proboscis at least 9 mm. long. These visitors cling to the corolla froi 

 below, and insert their proboscis into its narrow opening. They first touch 

 widely exserted siigma, and their proboscis then strikes against the anthers, bl 

 which they are dusted with pollen. 



Visitors. Herm. Mttller observed the humble-bee Bombus alticola Krchb. 

 the canton Graubtlnden. 



1989. C. minor L. (Herm. Mttller, 'Weit. Beob.,' HI, pp. 9-14.) In thi^ 

 species the nectar is less deeply hidden than in C. alpina, so that bees wit 

 a proboscis not less than 6 mm. long can reach the secreting base of the flowei 

 In doing this they hold on to the corolla-lobes with their first and second 

 of legs, further supporting themselves by placing the hind ones on the same 

 neighbouring flowers, or on the bracts. The anthers are borne on short 

 filaments, and their tips are closely applied to the style, while their margins 

 in contact. The base of each anther-lobe is produced into a filiform appenda^ 

 which interlocks with the corresponding appendage of the adjacent lobe of 



