70 TYPICAL FLOWERS OF ALPINE PASTURES 



Kerner states that the wax on the lower side of 

 the leaf tends to protect the plant by hindering the 

 access of water to the minute pores or stomata which 

 exist on the lower surface of the leaves of the rosette, 

 placed close to the ground. Were the leaves to 

 become saturated with water, the gases of the atmo- 

 sphere would no longer have free access to the leaf, 

 and thus the whole internal economy of the plant 

 would come to a standstill. The presence of a layer 

 of wax prevents the lower surface from becoming 

 easily wetted. This can be demonstrated by immers- 

 ing a leaf in water for a few minutes. It will then be 

 found that whereas the upper surface, where there is 

 no wax, is easily wetted, the lower remains quite dry. 



The Auricula {Primula auricula, Linn.) (Plate 

 XIV., Fig. 1) is, as we have said, one of the original 

 parents of our cultivated Auriculas. The Primulas, 

 as a whole, are very apt to form hybrids — that is, 

 crosses between, not two individuals of the same 

 species, but of two different species. Our garden 

 Auriculas are all derived from a cross between P. 

 auricula, Linn,, and P. hirsuta, All., which gives 

 a hybrid (P. pubescens), and this is the stock from 

 which yet other hybrids can be obtained. 



The hybrid, as we should expect, combines the 

 characters of both parents. The corolla limb is partly 

 yellow and partly red or violet, the yellow colour 

 being derived from the Auricula, the red or violet from 

 the other parent. The question of the inheritance of 

 characters in hybrids is a very interesting one, and 



