ON THE MIXED HERBAGE OF PERMANENT MEADOW. 
1275 
thus growing in association, are, therefore, those tinder which the luxuriance of its 
neighbours is restricted. In recent seasons, probably owing to the wetness, and to the 
increased growth of the grasses, it has decreased on all the plots ; and on the whole it 
is the most abundant on plot 6 (mineral manures after ammonia). 
Carduus arvensis. 
This, the commonest of the Thistles, on arable or on waste land, has a perennial, 
creeping rootstock, sending up annual stems, with prickly leaves, and heads of flowers, 
male on one plant, female on another. It was not, in any one separation-year, observed 
on more than two plots; and the only samples in which it was found were those from 
plot 18 (with the mineral constituents and nitrogen of one ton of hay), in 1867, and 
from plot 7 (mixed mineral manure including potass), in each of the four separation- 
years; and it only once reached as much as 0*26 per cent, of the total herbage. It 
would appear that this plant requires liberal supplies of mineral constituents near 
the surface, but that it cannot withstand the competition of luxuriantly growing 
associates. 
Beilis perennis. 
The common Daisy is well fitted to hold its own, or to spread, where circumstances 
permit. It has a perennial tufted stock, emitting numerous, rather fleshy, root-fibres, 
and branching at the top into numerous subdivisions. Sometimes, moreover, it gives 
off long shoots, appressed to the ground, and with a tuft of leaves at the end, capable 
of becoming a distinct plant. The leaves being flatly pressed to the ground, prevent 
the growth of plants beneath their shade. 
This persistent lawn-weed has only been observed on from five to eight plots out of 
the 22; and it only came into the samples in 1862 from two, in 1867 from five, in 
1872 from six, and in 1877 from five plots. It was found in extremely insignificant 
amount on three of the nitrate of soda plots, but not on any ammonia plot, or even 
where there was full mineral manuring. It occurred but in extremely small amount 
in each separation-year in the samples from one of the unmanured plots; again, in 
each separation-year, on the plot with superphosphate of lime alone; and in the last 
three separation-years on plot 1, after the discontinuance of the dung. It thus did 
not hold its own wherever there was any luxuriant growth of other plants. The 
contrary result on lawns is coincident with precisely contrary conditions of growth of 
the general herbage; in addition to which, it may be pointed out that the scythe or 
the mowing machine mutilates the appressed daisy leaves much less than it does the 
herbage of taller-growing species. 
