6o VIOLA. [chap. 



hollow spur (Fig. ^7 f), the entrance to which is pro- 

 tected partly by the stigma, partly by two tufts of 

 hairs, or rather of delicate lobular processes, situated 

 on the two median petals. The stamens consist of 

 a short filament, to which the anther is attached, and 

 a terminal membranous expansion, while the two 

 lower stamens also send out each a long spur 

 (Fig. S8«), which lies within the spur of the median 

 petal, and secretes honey at its fleshy end. The ter- 

 minal membranous expansions of the five stamens 

 slightly overlap one another, and their points touch 

 the pistil, so that they enclose a hollow space. The 

 pollen differs from that of most insect-fertilised 

 flowers, in being drier, and more easily detached 

 from the anthers ; consequently, when the latter 

 open, the pollen drops out ; and as the flower is 

 reversed and hangs down, the pollen falls into the 

 closed space between the pistil and the membranous 

 terminations of the stamens. The pistil is peculiar, the 

 base of the style not being straight as usual, but thin 

 and bent (Fig. 57). The stigma st is the enlarged 

 end of the pistil ; and shows several small fleshy pro- 

 jections. It will be obvious from the above description 

 that when a bee visits the flower, her head will come in 

 contact with and shake the stigma, thus opening, as it 

 were, the box containing the pollen, and allowing it 

 to fall on the head of the bee. It is thus carried 

 away, and some can hardly fail to be deposited on the 

 stigma of the next violet which the bee visits. 



Sprengel, in his description of V. odorata, gives the 

 following list of questions and answers as regards this 

 species ; passing over, however, the more general points, 



