THE ALPINE GENTIANS 47 



thus impossible to enter into the matter here, though 

 it may be stated that in some cases the white flowers 

 occasionally found are instances of fresh variations ; 

 whereas in others, the lack of a colour pigment in the 

 petals, or the development of an exceptional pigment, 

 may represent a reversion to an ancestral type. At 

 any rate, these variations in colour have no connection 

 with the chemical nature of the soil, as was formerly 

 thought possible, but they arise from deep-seated 

 tendencies, which find their expression in the exist- 

 ence of the individual, and the evolution of the race. 



But to return to the Alpine Gentians : we will 

 commence with the blue-flowered species, which are 

 universally regarded as among the most interesting of 

 Alpine plants. These fall naturally into three groups. 

 First we have the Gentians with star-like flowers. 

 The corolla formed by the united petals consists of a 

 narrow tube below, the free portions of the petals 

 expanding above into radiating lobes, which, when 

 the flower is open, are spread out nearly at right 

 angles to the tube. Between the free portions of the 

 petals, small lobes occur, each divided into two. 

 When the flower is closed, the free portions of the 

 petals point upwards and are twisted together. The 

 Spring, Bavarian, and Snow Gentians belong to this 

 group. In these the leafy stem is short, though it is 

 quite obvious. 



Next we have the Bell Gentians with very short 

 stems, and corollas in the form of a large bell, 

 the mouth pointing upwards to the sky when the 



