"•U 



558 



REPOHT — 1884. 



Singularly enough, this deficiency of herbaceous plants is being sup- 

 plied from Eui'ope, and the incomers are spreading with great rapidity ; 

 for lack of other forest material even apple-trees are running wild and 

 forming extensive groves. Men and cattle are, as usual, the agents ot 

 dissemination. But colonizing plants are filling, in this instance, a vacancy 

 which was left by nature, while onra was made by man. We may agree 

 with Mr. Ball in the opinion that the rapidity with which the intrusive 

 plants have spread in this part of South America ' is to be accounted for 

 less by any special fitness of the immigrant species, than by the fact that 

 the ground is to a great extent unoccupied." 



The principle applies here also ; and, in general, that it is opportunity 

 rather than specially acquired vigour tliat has given Old-World weeds an 

 advantage may be inferred from the behaviour of our weeds indigenous 

 to the country, the plants of the unwooded districts — prairies or savannas 

 west and south, which, now that the way is open, are coming in one by 

 one into these eastern parts, extending their area continually, and holding 

 their ground quite as pertinaciously as the immigrant denizens. Almost 

 every year gives new examples of the immigration of campestrine western 

 plants into the Eastern States. They are well up to the spirit of the age; 

 they travel by railway. The seeds are transported, some in the coats of 

 cattle and sheep on the way to market, others in the food which supports 

 them on the journey, and many in a way which you might not suspect, 

 until you consider that these great roads run east and west, that the 

 prevalent winds are from the west, that a freight-train left unguarded Avas 

 not long ago blown on for more than one hundred miles before it could 

 be stopped, not altogether on dov\ n grades, and that the bared and mostly 

 unkempt borders of these railways form capital seed-beds and nursery 

 grounds for such plants. 



Returning now from this side-issue, let me advert to another and, I 

 judge, a very pleasant experience which the botanist and t..e cultivator 

 may have on first visiting the American shores. At almost every step he 

 comes upon old acquaintances, upon shrubs and trees and flowering herbs 

 mostly peculiar to this countiy, but with which ho is familiar in the 

 grounds and gardens of his home. Great Britain is especially hospitable 

 to American trees and shrubs. There those both of the eastern and 

 Avestern sides of our continent flourish side by side. Here they almost 

 wholly refuse such association. But the most familiar and longest- esta- 

 blished representatives of our flora (certain western annuals excepted) were 

 drawn from the Atlantic coast. Among them are the Virginia creeper 

 or ampelopsis, almost as commonly grown in Europe as here, and which, 

 I think, displays its autumnal crimson as brightly there as along the 

 borders of its native woods where you will everywhere meet with it ; the 

 red and sugar maples, which give the notable autumnal glow to our 

 northern woods, but rarely make much show in Europe, perhaps for lack 

 of sharp contrasts between summer and autumn ; the ornamental erica- 

 ceous shrubs, kalmias azaleas, rhododendrons, and the like, specially 

 called American plants in England, although all the rhododendrons of 

 the finer sort are half Asiatic, the hardy American species having been 

 crossed and rccrossed with more elegmt but tender Indian species. 



As to flowering herbs, somewhat ot the delight with which an American 

 first gathers wild primroses and cowslips and foxgloves and daisies iu 

 Europe, may be enjoyed by the European botanist when he comes upon 

 our trilliums and sanguinaria, cvfiripodiums and dodecatheon, our species 



