376 



LESSONS WITS PLANTS 



474. As reproduction by asexual or vegetative 

 means increases, seed -production tends to decrease. 

 There are many kinds of plants 

 which are normally nearly or quite 

 seedless, but such plants are al- 

 ways provided with vegetative means 

 of propagation. Manj of the pond- 

 weeds are of this class ; so are the 

 horse-radish, banana, pineapple and 

 pepino. Even the Canada thistle 

 bears comparatively few seeds, al- 

 though it blossoms profusely ; but 

 it propagates rapidly by underground 

 parts. 



475. If nature is so free and 

 undogmatic in her methods of propa- 

 gation, surely man can devise al- 

 most numberless ways in which to 

 multiply his plants. Every plant 

 which propagates from seeds slowly 

 or with difficulty and which is de- 

 FiG. 397. sired to be cultivated man propa- 



piantiets on begonia gates in some manner by asexual 



stem. 



parts ; and it is probable that 

 every plant can be so multiplied, upon occasion. 



476. Of most plants, a bit of soft stem with 

 one or two joints and a leaf or two will grow 

 when severed and placed in the ground under 



