CHAPTER XIY. 



Asexual Reproduction. 



§ I. Artificial Division. — Weeping willows are by no means 

 scarce trees in Britain, yet as they never flower, they must all have 

 grown from slips, or in other words artificial asexual multiplica- 

 tion. So too, only more naturally, the Canadian pond-weed has 

 spread prodigiously in our lochs, canals, and rivers, never 



A group of Sea- Anemones.— From Andres. 



flowering, but owing its increase wholly to the asexual process. 

 Every one knows how the gardener increases his stock by slips 

 and cuttings, thus taking advantage of the power a part has to 

 reproduce the whole. Quite in the same way, cultivators of 

 bath sponges bed out litde fragments to keep up a convenient 



