54 TYPICAL FLOWERS OF ALPINE PASTURES 



take place in the following manner and circumstances. 

 The ordinary method, described above, depends to 

 some extent on the occurrence of fine sunny weather, 

 when the flowers are mature. If the summer is wet, 

 bees are not on the wing and the flower remains 

 closed. In this case the pollen, when mature, falls to 

 the bottom of the bell and there accumulates. Later, 

 when the stigmas are ripe, the stalk of the flower 

 lengthens, and the closed bell, instead of pointing 

 directly upwards, is inverted. The pollen falls down 

 along the grooves inside the folded bell, and thus, 

 when the bell is shaken by the wind, reaches the 

 stigmas, and the plant is self-fertilised. This process 

 may also occur at night, when the flowers are always 

 closed. 



Thus the diff*erence in the position of the bell of 

 this Gentian, whether held vertically upright or 

 pointed earthwards, has an important biological 

 significance. The two positions may be observed 

 in almost any large patch of this plant in the Alps. 



The Fringed Gentians, or Gentianellas. 



We now reach our third group of blue-flowered 

 Gentians, the Fringed Gentians, or Gentianellas, which 

 possess a fringe of much-divided scales just inside 

 the throat of the corolla. The Field Gentian {Gentiana 

 campestris, Linn.), a fairly common British plant, and 

 the Delicate Gentian {Gentiana tenella, Rottb.), a 

 somewhat rare High Alpine, are the two chief repre- 

 sentatives of this group in Alpine Switzerland. 



