THE FLOWER OF TIIF PANSY 161 



Of the five petals, one is larger than tlio rest, and 

 serves as a landing-stage for the bees and bntterHies 

 visiting the flower in search of the nectar, which 

 is hidden away in the spur or backward tubular 

 prolongation of the large petal. The bright colours 

 of the petals, as a whole, serve to attract these insects, 

 and the numerous streaks or lines of colour, all 

 leading to the centre of the flower, serve as '' honey 

 guides," directing the insect to the narrow opening at 

 the mouth of the flower, through which the knob- 

 like stigma projects. If we dissect away the petals, 

 we shall expose the five anthers, which are mounted 

 on very short stalks, and closely ap{)lie(l to the 

 ovary. The anthers open inwards towards the pistil, 

 and above each anther a membranous appendage is 

 found. From the bases of two of the stamens, two 

 glistening, white, spur-like nectai'ies, secreting honey, 

 hang freely in the spur of the large petal. They will 

 be easily seen if the spm* is carefully slit open. In 

 the centre of the flower, the ovary is produced 

 upwards into a club-shaped hairy stigma, on one side 

 of which is a small pit or groove, below which a little 

 triangular tiap or valve can be seen. The stigmatic 

 surface is situated in this groove. 



Now let us imagine that a bee or butterfly has 

 just alighted on the large petal. As it thrusts its 

 tongue or proboscis into the opening of the Hower to 

 get at the honey in the spur, any pollen, derived from 

 a previously visited flower, adhering to its head comes 

 into cont<act with the stigmatic surface, whicli lies in 



