VARIOUS MARRIAGE CUSTOMS. 89 



Even in our own day, in plants where stamens 

 are numerous, they often tend to develop into 

 petals, especially when growing in very rich soil, 

 or under cultivation. This is what we call " doub- 

 ling " a flower. In the double rose, for example, 

 the extra petals are produced from the stamens of 

 the interior, and if you examine them closely you 

 will see that they often show every possible grada- 

 tion and intermediate stage, from the perfect sta- 

 men to the perfect petal. The same thing read- 

 ily happens with buttercups, poppies, and many 

 other flowers. We may take it for granted, then, 

 that petals are, in essence, a single outer row ot 

 stamens, flattened and coloured, and set apart by 

 the plant to advertise its honey to insects, and so 

 induce them to visit and fertilise it. 



In the largest and most familiar group of flow- 

 ering plants, to which almost all the best-knoivn 

 kinds belong, the original number of petals seems 

 to have been five; and we will take this number 

 as regular for the present, explaining separately 

 those cases where it is exceeded or diminished. 

 The common ancestor of all these plants, we may 

 conclude, had all its parts in rows of five. Thus 

 it had five, ten, or fifteen carpels in its pistil that 

 is to say, one, two, or three rows of five carpels 

 each ; it had five, ten, or fifteen stamens, it had 

 rive or ten petals, and it had a calyx, outside all, 

 of five sepals. We will now proceed to examine 

 in detail some of the many curious marriage cus- 

 toms which have arisen among the group of plants 

 that started with this ground-plan. 



One great family of plants which early divided 

 itself from this great central stock is the family 

 of the buttercups. Our common English bulbous 



