2 1 6 SJ GA CITY AND MORALITY OF PLANTS. 



to the same variability ; and this is, perhaps, more 

 notable in the woody kinds than in herbaceous, 

 although it is abundantly exemplified in the latter. 

 Of course we cannot tell to what dimensions the 

 original ancestor of any plants grew ; and doubtless 

 we should find that the progeny of all have experi- 

 enced varying successes and reverses like those the 

 human descendants of Charlemagne and Alfred have 

 gone through, if we could formulate them. Some 

 may have attained a huger bulk than their fore- 

 runners, and probably this is usually the case ; but 

 many others have retrograded. Still, the number of 

 the latter cannot exceed that of the former, any 

 more than paupers can form the bulk of the popula- 

 tion. These botanical waifs and strays may even 

 throw some light on the evolution of their kind, and 

 picture to us the physical experience they have 

 undergone ; as witness the order of the Willows 

 {Salicacecs), even within the bounds of the genus 

 Salix, all of whose species must have had a common 

 origin. These members vary from the White Willow 

 {Salix alba — Constable's Queen of the Meadows), 

 seen so abundantly in our river-valleys, to the Least 

 Willow {Salix kerbacea), found only on the bleak 

 tops of the Scottish mountains, where it never 

 exceeds the length of six inches ! What a story 

 does this difference in size tell of opposite conditions 

 of life — the dwarf species fighting it out on the 

 bleak and exposed mountain -top, amid frosts and 



