ON THE MIXED HERBAGE OE PERMANENT MEADOW. 
1399 
which, had gained, both in actual and relative amount, compared with 16, by the 
second separation-year. Indeed, so far as the actual yield of the different grasses is 
concerned, the two newer plots in the main approximated to the character of the 
older one. 
So far as the actual yield of the leguminous species is concerned, the most marked 
distinction between the older plot and the two newer ones is, that on the latter, 
Lathyrus pratensis is in considerable deficiency, whereas the different species of 
Trifolium have been hitherto mostly in excess. 
Looking to the actual yield of the miscellaneous species, Conopodium denudatum 
alone comes to yield markedly more on the newer than on the older nitrate of soda plot, 
most of the other species yielding less. With the nitrate of potass, on the other hand, 
Ranunculus repens and bidbosus, as well as Conopodium denudatum , yield an excess. 
The last three columns of the table bring to view the excess or deficiency in actual 
yield of each group or species of plant on plot 20 as compared with plot 19. They show 
that on plot 20, with the nitrate of potass, there was among the grasses a strikingly 
greater tendency to increase in the comparatively shallow-rooting Holcus lanatus , and 
some tendency to increase in Lolium perenne, Alopecurus pratensis , Arena flavescens, 
Agrostis vulgaris , and Anthoxanthum odoratum. There was, however, with the nitrate 
of potass a tendency to less produce of Poa trivialis, Dactylis glomerata , Festuca 
ovina, Cynosurus cristatus, and Arena pubescens. But the differences are, excepting 
in the very marked instance of the Holcus, too small to be thoroughly relied on in 
forming a judgment as to the different tendencies on the two plots. 
Of total Leguminosae there was notably less on plot 20 than on plot 19. There was, 
somewhat characteristically, a deficiency of the deeply-rooting Trifolium pratense ; but 
there was at the same time a greater deficiency in the more surface-feeding Lathyrus 
pratensis. 
Comparing the actual yield of miscellaneous species on plot 20 with that on plot 19, 
the most striking differences are, that with the less rapidly diffusing nitrate of potass, 
the comparatively superficially-rooting Ranunculus repens and bidbosus give a con¬ 
siderable excess, whilst the more deeply-rooting Conopodium denudatum and Rumex 
Acetosa are relatively in defect. 
Taking the whole period of nine years, the general result has been that, with equal 
nitrogen on the three plots, but with more mineral supply on plot 16, which has also 
been under the same conditions of experiment for 14 preceding years, it showed 
annually more total growth, that is, yielded more total produce, containing more 
nitrogen, and more total mineral constituents, than either of the newer plots 19 or 20. 
Again, plot 19, with rather fuller mineral supply than plot 20, has yielded slightly 
more produce, more nitrogen, and more mineral matter. The deficiency of total growth 
on the newer plots was chiefly in the grasses, but somewhat in the Leguminosae also. 
Upon the whole, the tendency of change on the new plots was such as to bring 
them more nearly to the condition of the older one. All three plots, with only 
8 Q 2 
