BITING STONECROP 159 



Three to six inches is the usual height for this pretty but diminutive 

 species, which flowers in June and July. It is perennial, attractive, 

 and suited for cultivation, and can be increased by division. 



The plant is short, but the flowers are conspicuous on barren 

 ground where it grows. It is proterandrous and contains honey, 

 accessible to short-lipped insects, whence it is much visited. The 

 honey is secreted in 5 yellow scales at the base of the flowers between 

 the anthers and carpels. The flowers are cross-pollinated. When the 

 flower opens and the petals spread into a star, 5 outer stamens alter- 



BITING STONECROP (Sedum acre, L.) 



nate with the petals, and are erect, and now open in the middle of the 

 flowers, and the 5 others are inclined outwards while the petals remain 

 closed, and the stigmas are still immature. As the first stamens wither 

 and turn outwards, the others rise up into the centre and open. Before 

 the second ring withers and turns outwards, the stigmas ripen and 

 stand in the centre. Insects remove the pollen before the stigmas are 

 mature, but in dull weather the anthers are stored with pollen till the 

 stigmas are ripe and may self-pollinate the flower. 



Insects touch the stamens and stigmas whether they settle in the 

 centre or on the edge of the flowers. The flowers are visited by 

 Bombus, Cilissa, Andrena, Sphecodes, Nomada, Prosopis, Megachile, 

 Ammophila, Oxybelus, Eristalis, Pyre Ilia. 



The follicle is many-seeded and opens above, and the seeds are 

 dispersed by the wind. 



