1290 
MESSRS. J. B. LAWES, J. H. GILBERT, AND M. T. MASTERS, 
I he Botany of each separate plot, in each Season of Complete Separation. 
Thus far we have described the arrangement of the experiments, the mode of 
experimenting, and the characters of the seasons preparatory to and during the periods 
of growth of the four crops selected for complete botanical separation; we have given 
a complete list of all the plants, either found in the samples or observed growing on 
any one of the whole series of 20 (or more) plots; we have called attention to the 
general prevalence of certain plants, and to the characters, structural or physiological, 
above-ground or under-ground, which may be supposed to influence the results of 
the struggle, when numerous species are growing in association, and when conditions 
are provided which unequally affect the activity of growth of the different components 
of the mixed herbage. Finally, the actual or relative characteristics of growth of each 
species found in the samples, or observed on the plots, have been briefly described; 
and it has been pointed out, under what conditions of manuring each has maintained 
or improved its position, or has succumbed in the combat with its associates under the 
more active competition which has been induced. 
It remains to describe the botanical composition of the collective herbage of each 
of the differently manured plots, in each of the four seasons of botanical separation; to 
direct attention to the changes in the flora, from one separation-year to another, under 
the different conditions; and to consider the character of the changes—whether 
apparently progressive and regular, and probably due almost exclusively to the con¬ 
ditions induced by exhaustion or by manuring; or whether they are probably 
materially influenced by the characters of the seasons to which the associated species 
have been exposed. . 
It is obviously essential, as a means of discriminating between the results primarily 
due to the conditions of manuring, and those greatly dependent on the characters of 
the seasons of growth, to bear in mind what were those characters, and what was the 
nature of their influence in determining to luxuriance or to maturation, and so on. It 
will be desirable, therefore, as a preliminary to the discussion which is now to follow, 
very briefly to summarise in this place the climatal characters of the different seasons, 
referring for more detail to the fuller consideration of the subject at pp. 1188-1206. 
First season of separation, 1862,—This, the first season of complete botanical 
separation, was the seventh in the course of the experiments. Dependent on previous 
conditions, there were full average second crops in 1861. The autumn and winter of 
1861-2 were warmer and drier than usual, excepting November, which was cold and 
wet. In 1862 the grass-growing months were wetter than the average, and also 
warmer, excepting June, which was wet and cold, protracting growth, but not maturing. 
The experimental crops were generally considerably over the average. The climatal 
conditions were favourable to the prominence of the grasses, especially of the freer- 
growing ones, also of free-growing weeds, and especially Rumex Acetosa, Conopodium 
denudatum , and Achillea Millefolium. The herbage was characterised by abundance 
