ON THE MIXED HERBAGE OF PERMANENT MEADOW. 
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depends, as pointed out by A. P. Ca.ndolle, % in a great measure on the number of its 
foes or of its allies among the animals and plants inhabiting the same region. Thus, 
for example, a plant which loves the shade may multiply, if some tree with spreading 
boughs and dense foliage flourish in the neighbourhood. Another, which if unassisted 
would be overpowered by the rank growth of some hardy competitor, is secure because 
its leaves are unpalatable to cattle, whilst they annually crop down its antagonist, and 
rarely suffer it to ripen its seed. 
The same author, in his ‘ Physiologie Vegetale,’ tom. iff., p. 1471, in alluding to the 
relative development of the root fibrils in different plants, points out that when in any 
given area there are several individual plants of different degrees of vigour, the roots 
of the stronger will deprive those of the weaker of their nourishment, and that this 
inequality of action will confer an advantage on the first comer. 
Some experiments bearing directly on the struggle among plants have been made 
by Professor Hoffmann, of Giessen,! who watched the changes among plants growing 
together, and endeavoured to ascertain what were the circumstances which contributed, 
to the success of the victors. In a previous set of experiments it had been found that 
the particular plants under observation grew equally well in different kinds of soil, 
provided due care were taken to prevent the growth of intruding weeds. Having 
arrived at this result, the several plants were left to themselves, with a view of 
determining how they would comport themselves without assistance against the 
inroads of weeds. It resulted that the weeds completely gained the ascendancy. The 
species which held out longest was Asperula cynanchica. This plant, after having 
been grown in a bed for three years, and protected from weed invasion by the use of 
the hoe, was then left to take care of itself. It held out for some four years, but was 
ultimately elbowed out by the intruders. 
Professor Hoffmann then set himself to observe the results of the internecine 
struggle between the weeds themselves, thinking that the ultimate survivors would 
perhaps prove to have special affinities for the soil in which they grew. Thus left to 
themselves the beds became so densely covered that in a square foot 460 living 
plants, and the remnants of many others which had succumbed, were counted. 
Every year in July the beds were examined, and every year the number of species 
was found to have diminished, till at length only a few were left; and these not only 
persisted, but slowly gained ground from year to year, and ultimately remained in 
possession of the plot. 
Of 107 species under observation, all, or nearly all, found the most essential 
requisites of their existence equally well in all the varieties of soil, so that, other condi¬ 
tions being equal, the nature of the soil was indifferent. The species which remained 
victors, all the others being ultimately dispossessed, were Triticwn repews, Poa 
pratensis, Potentilla reptans, Acer pseudo-platanus, Cornus sanguined, native plants ; 
* Cited by Lyell, ‘ Principles,’ vol. ii., ed. 10 (1868), p. 435. 
t See ‘ Botanische Zeitung ’ (Beilage), 1865, and ‘ Landwirthschaftliches Wochenblatt des Ackerban- 
ministeriums in Wien,’ 1870 ; see also ‘ Gardeners’ Chronicle,’ 1870, p. 664. 
7 R 2 
