OBSERVATIONS ON FLORAL CHANGES. 77 



beginning with the earliest records of the British Flora, and tracing its history 

 up to the present time, we find that there has been a gradual and steady increase 

 in the number of such interlopers. At the present time a very considerable 

 portion of our Flora consists of such plants — species which are supposed to 

 have originally belonged to distant countries, but which the commerce and 

 agricultural operations of mankind have been the means of introducing to 

 Britain, and thus extending, in some cases in a very remarkable manner, their 

 geographical range. Some of these plants, such as Mimidus luteus, for instance, 

 are clearly known to have been directly introduced to this country by the 

 hand of man, although now perfectly naturalized with us; while a considerable 

 number cannot be so distinctly shewn to owe their introduction to mankind. 

 The Anacharis Alsinastnim, a plant which has been discovered of late years 

 in this country, belongs to the latter class; and although the great abundance 

 in which it was found in many widely-separated localities, led botanists at first 

 to accord to it an undisputed place in the British Flora, yet the more we 

 learn of this interesting aquatic, the more probable does it seem to be an 

 exotic importation. 



It is sufficiently ungrateful for the generality of the botanists of the present 

 day to discard, in the manner they do, all plants which have recently appeared 

 in our land under such suspicious circumstances, as well as a number of others, 

 which in the earlier days of our science, were implicitly regarded by the 

 unsuspecting recorders of our Flora as indigenous productions. It is diflicult 

 to say how far botanists are right in so doing; for my own part, I do 

 not readily accede to this strong disposition to regard many of our most 

 beautiful native flowers as aliens — a disposition by no means evinced in the 

 same degree by the botanists of any other age or country. Bromfield, in 

 speaking on this subject, has some very judicious remarks: — "\ do not," he 

 S£iys, "on the perusal of the writers of Continental Floras, (an extensive 

 collection of which, old and new, I am much in the habit of consulting,) 

 find the same disposition to doubt the origin of species, which seems so 

 peculiarly to characterize the botanists of this country, that they must needs 

 have recourse to the hypothetical agency of birds, monachism, garden escapes, 

 and other problematical and unproved operative causes, to account for the 

 dissemination of half the plants of our country, whose flowers are a little more 

 specious in appearance than ordinary, without considering that Nature, in her 

 beneficence, has not left the most hyperborean regions, or the most sterile 

 wastes, unadorned by some rare and lovely floral productions, to gladden the 

 general desolation; while she scatters with a yet more unsparing hand her 

 richest gems over temperate and fertile countries. Cast a glance over the 

 inhospitable and frigid Siberia, or the Altaic chain of mountains, and the 

 vast plains at their feet, where the mean temperature of the interior of the 

 earth's crust is but little above the freezing point the year through, yet what 

 an array of even southern types of vegetation does the short and not very 

 warm summer, of some five months duration at most, unfold to the botanical 



