42 THE EVOLUTIONIST AT LARGE. 



which growth can possibly take place under 

 their circumstances. Of course, however, the 

 particular pattern of leaf depends largely 

 upon the ancestral form. Thus this crowfoot, 

 even in its submerged leaves, preserves the 

 general arrangement of ribs and leaflets 

 common to the whole buttercup tribe. For 

 the crowfoot family is a large and eminently 

 adaptable race. Some of them are larkspurs 

 and similar queerly-shaped blossoms ; others 

 are columbines which hang their complicated 

 bells on dry and rocky hillsides ; but the 

 larger part are buttercups or marsh mari- 

 golds which have simple cup-shaped flowers, 

 and mostly frequent low and marshy ground. 

 One of these typical crowfoots under stress 

 of circumstances inundation, or the like 

 took once upon a time to living pretty perma- 

 nently in the water. As its native meadows 

 grew deeper and deeper in flood it managed 

 from year to year to assume a more nautical 

 life. So, while its leaf necessarily remained 

 in general structure a true crowfoot leaf, it 



