THE TWO-FLOWERED VIOLET 253 



shaped keel of the Leguminous flower, while the two 

 upper petals form a sort of standard. There are only 

 eight stamens, all united into a bent tube, split on 

 one side. In this, again, we find a curious resemblance 

 to the Pea family, where, however, there are ten 

 stamens. The anthers open by pores. The style 

 lies inside the tube of stamens, and is likewise bent 

 in conformity with the shape of the keel. 



The explanation of the curious parallelism between 

 the shape of the flower of this Polygala and that of 

 a Leguminous plant is to be sought for in the mode of 

 pollination. The whole structure of the flower is 

 adapted to that end, and though it differs in some 

 details, the manner of fertilisation is quite similar 

 to that of a typical member of the Pea family (see 

 p. 328). 



The Box-leaved Polygala has the distinction of 

 being the sole member of the genus, in which the 

 stem is woody, all the other species being herbaceous. 



THE TWO-FLOWERED VIOLET. 

 One of the most delicate and graceful plants of 

 the Alpine forests is the little Yellow-flowered Violet 

 (Viola biflora, Linn,, natural order Violacese, the 

 Violet family) (Plate XLVL, Fig. 2). This plant 

 loves the damp, shady dells among the Pines, where 

 it forms characteristic clumps. The slender shoots 

 bear usually two large, kidney-shaped leaves, quite 

 typical examples of shade-leaves (p. 247). They are 

 thin and delicate structures, light-green below, but 



