VA1UOUS MAEKIAGE CUSTOMS. 109 



Thus every pin-eyed blossom must always be 

 fertilised by a thrum-eyed, and every thrum-eyed 

 by a pin-eyed neighbour. This is one of the 

 most ingenious arrangements known for cross- 

 fertilisation. 



Much as I should like to dwell further on 

 these interesting cases, I must hurry on to 

 complete our rapid survey of a great subject. 

 Flowers like the harebell and the primrose are 

 tubular but regular. Other flowers with a 

 tubular corolla go yet a step further and are 

 irregular also. This irregularity, like that of 

 the monkshood, secures for them in the end 

 greater certainty of fertilisation. Two well- 

 known groups of this sort are the sages, on the 

 one hand, and the fox-gloves, monkey-plants, 

 and snap-dragons on the other. I shall mention 

 only one instance of special devices for cross- 

 fertilisation in these groups, that of the various 

 sages, beautifully seen in the large blue salvias 

 of our gardens. In this plant there are only two 

 stamens, though most of the group to which it 

 belongs have four, because the excellent ar- 

 rangements for fertilisation make this single 

 pair a great deal more effective than the thirty 

 or forty required by the common buttercup. 

 For the stamens are delicately poised on a sort 

 of lever, so that the moment the bee enters the 

 flower, they descend and embrace him, as if by 

 magic. While the stamens alone are ripe, this 

 continues to happen with each flower he visits ; 

 but when he goes away to an older blossom, he 

 finds the stigma ripe, and bending over into the 



