THE SAXIFRAGES 81 



with the petals. Then in a day or so, one of the ten 

 stamens becomes erect and moves in towards the 

 centre of the flower, where it remains until it has 

 shed its pollen on to the back of any insect that 

 may visit the flower in search of honey. At the 

 end of twenty-four hours or more, it bends back to 

 its original position, and not till then does the next 

 stamen begin to go through the same performance. 

 After all the ten stamens have shed their pollen 

 one by one in this way, and not until then, the two 

 stigmas of the ovary mature. Thus the female organs 

 of the flower cannot be fertilised by the pollen of the 

 same flower. 



As a typical example of the Saxifrages inhabiting 

 dry stony places, we may instance the Rough 

 Saxifrage (Saxifraga aspera, Linn.) (Plate XV.), which 

 is widely distributed in the Alps. It has a very near 

 relative, the Moss-like Saxifrage (S. bryoides, Linn.), 

 which is perhaps only a High Alpine variety of the 

 former. The flowering shoots of the Eough Saxifrage 

 are leafy, and the thick leaves are rough with long 

 hairs. 



Further, many of the leaves bear large leaf-buds 

 in their axils, which in the High Alpine (S. bryoides) 

 are as long as the leaves themselves. The flowers of 

 this species are also interesting botanically, from the 

 fact that the ovary is superior or free from the calyx 

 tube, whereas in the majority of Saxifrages the ovary 

 is more or less united with the calyx tube. 



The Eough Saxifrage, like all the other Swiss 



F 



