PRIMULACEAE 



79 



Herm. Muller {on pendula), a humble-bee and a beetle ; (on indinald) 3 Muscids 

 and a moth. Schulz, 20 bees (including Bombus alticola Krchb) and various flies 

 and beetles. 



1837. S. minima Hoppe. (Schulz, 'Beitrage,' II, p. 191.)— The conical 

 flowers of this species are 8-15 mm. long, and project almost at right angles 

 from the main axis, so that automatic self-pollination is rendered difficult in spite 

 of the homogamy. 



Visitors. — Schulz saw 2 bees and 7 flies. 



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X 



/ 



550. Cyclamen L. 



Protandrous pollen flowers, from which visitors perhaps obtain sap by boring 

 the delicate tissue of the corolla-tube. The anthers make up a sprinkling arrange- 

 ment, as in Borago. 

 Their lobes dehisce by 

 terminal pores, and 

 are produced into stiff 

 appendages against 

 which visitors strike. 

 Automatic self-pollina- 

 tion is ultimately ef- 

 fected by strong down- 

 ward inclination of the 

 peduncle, bringing the 

 stigma into the line 

 of fall of the pollen 

 {cf. Fig. 250). 



According to Hil- 

 debrand (Ber. D. bot. 

 Ges., Berlin, xv, 1897, 

 pp. 292-8), the species 

 of Cyclamen are at 

 first entomophilous and 

 afterwards anemophi- 

 lous, as in the cases of 

 Calluna vulgaris, Erica 

 carnea, and Bartsia 

 alpina described by 

 Kerner('Nat.Hist.Pl.,' 

 Eng. Ed. I, II, p. 129). 

 The pollen-grains are 

 at first covered by sticky 

 oil, but later on cease 

 to be adhesive and 

 become pulverulent. Although the anthers usually dehisce in the bud autogamy 

 cannot take place, partly owing to the initial stickiness of the pollen and partly 



Fig. 250. Cydavicti laii/oliiwi, Siblh. ei Sju. (from Kerner, after Ascher- 

 son). A. Diagram of the parts of the flower at the beginning of anthesis. 

 The direction in which the pollen falls is far removed from the stigma. B. Do. 

 at time of complete development. By further bending of the peduncle the line of 

 fall of the pollen is brought nearer the stigma. C. Do. at the end of anthesis. 

 The stigma is now in the line of fall of the pollen, a, peduncle; b, cone of 

 anthers : c, line of fall of the pollen ; d, c, direction of basal and terminal parts 

 of the peduncle (and of the style). 



