on The mixed herbage of permanent meadow. 
1293 
with little undergrowth, until, with warm weather in June, the herbage thickened 
surprisingly, yielding, eventually, more than average produce, especially on the highly- 
manured plots, where free-growing grass prevailed. There was, however, considerable 
irregularity of development, excepting with the nitrate of soda. 
Thus, between the third and fourth separation-years, 1872 and 1877, there were 
several seasons of more or less ungenial weather for the growth of first crops, which 
were only average or under average; and those of the second year were both under 
average and much damaged by the dryness and coldness of the growing period. The 
second crops of the period were, however, over average, and those of the third inter¬ 
mediate season (1875) were not only very heavy, but were removed from the land. 
Finally, the year of separation itself was one of early promise, then checked growth, 
but eventually luxuriant and heavy produce, with, however, very uneven development 
on the different plots. The general result was an increased proportion of gramineous 
herbage, especially of the freer-growing grasses, where there was liberal manuring. 
1. Without manure; Plots 3 and 12. 
Before describing in detail the botany of the manured plots, it is essential to study 
carefully that of the unmanured plots 3 and 12, both separately and comparatively. 
We shall thus gain an idea of the natural vegetation of the experimental area. By 
comparing the composition of the herbage on one plot with that on the other, we shall 
be able to form an approximate estimate of the range and the limits of variation on 
ostensibly duplicate areas; and by comparing the results of one year with those of 
another, we shall learn something of the character of the changes induced by variations 
of season, by the constant competition and struggle, and by progressive exhaustion, 
irrespectively of the influence of manure. Further, we shall acquire standards with 
which to compare the results obtained on the manured plots. 
The following Tables LXIII. and LXIY., pp. 1294, 1295, give a complete numerical 
record of the botany of the two unmanured plots, in each of the four separation-years. 
In Table LXIII. is given the number of species found in the samples, grouped as 
“Graminese,” “Leguminosse,” and "Other Orders” (all the miscellaneous species being 
arranged under this heading); in it the percentage of each species in the total mixed 
herbage is also recorded. In Table LXIV. the actual quantity of each species, in lbs. 
per acre, is given. The mean results for each plot over the four years, as well as the 
difference between the one plot and the other, are also shown. 
Mdccclxxxh. 
8 d 
