422 



SCIENCE 



[N. S. Vol. XXXII. No. 822 



are not admitted, though they may be met 

 with here and there well established, and 

 at least as likely to perpetuate their spe- 

 cies in the new home as are some native 

 species. 



Comparatively few writers seek to 

 analyze the floras of the districts treated 

 of with a view to determine whence each 

 species came and how, its relation to man, 

 whether assisted by him in its arrival di- 

 rectly or indirectly, whether favored or 

 harmfully affected by him, its relations to 

 its environment — especially to other 

 species of plants and to animals, and 

 other questions that sviggest themselves 

 when such inquiries are entered on. It is 

 very desirable that a careful and exhaus- 

 tive revision of the British flora should be 

 made on these and similar lines. In such 

 a revision it is not less desirable that each 

 species should be represented by a good 

 series of specimens, and that these should 

 be compared with similar series from 

 other localities within our islands, and 

 from those countries from which it is be- 

 lieved that the species originally was 

 sprung. Such careful comparison would 

 probably supply important evidence of 

 forms being evolved in the new environ- 

 ments, differing to a recognizable degree 

 from the ancestral types, and tending to 

 become more marked in the more distant 

 and longer isolated localities. An excel- 

 lent example of this is afforded by the 

 productive results of the very careful in- 

 vestigation of the Shetland flora by the 

 late Mr. W. H. Beeby. 



Within recent years excellent work has 

 been done in the study of plant associa- 

 tions, but the reports on these studies are 

 dispersed in various journals (often not 

 botanical), and are apt to be overlooked 

 by, or to remain unknown to, many to 

 whom they would be helpful. The same is 

 true in large measure of the very valuable 



reports of work done on plant-remains 

 from peat-mosses, from lake deposits, and 

 from other recent geological formations, 

 researches that have cast such light on the 

 past history of many species as British 

 plants, and have proved their long abode 

 in this country. Mr. Clement Reid's 

 "Origin of the British Flora," though 

 published in 1899, has already (by the 

 work of himself and others) been largely 

 added to, and the rate of progress is likely 

 to become still more rapid. Among the 

 fruits and seeds recorded from interglaeial 

 and even from pregiacial deposits are 

 some whose presence could scarcely have 

 been anticipated, e. g., Eypecoum pro- 

 cumbens, in Suffolk. Some of the colon- 

 ists, or aliens now almost confined to 

 ground under cultivation, have been re- 

 corded from deposits that suggest an 

 early immigration into the British Is- 

 lands. While much remains to be discov- 

 ered,, it is desirable that what is already 

 established should find a place in the man- 

 uals of British botany. 



Apart from the descriptive and topo- 

 graphical works and papers on our flora, 

 there is a serious lack of information 

 gained from the study of our British 

 plants. Although a few types have re- 

 ceived fuller study, we have little to com- 

 pare with the work done in other countries 

 on the structure and histology of our 

 plants, on the effects of environment, on 

 their relations to other species and to ani- 

 mals, and on other aspects of the science to 

 which attention should be directed. On 

 these matters, as on a good many others, 

 we gain most of what information can be 

 had not from British sources, but from 

 the literature of other countries, though 

 it is not wise to assume that what is true 

 elsewhere is equally true here. It is as 

 well, perhaps, that for the present such 

 subjects should find scanty reference in 



