Mixed Herbage of Grass-Land. 
133 
Ammonia-salts, on the other hand, which produce such 
characteristic effects upon the growth of the Graminaceous plants 
of the mixed herbage, have also a marked influence upon that of 
the Graminaceous plants grown separately in rotation, and but 
little on that of the Leguminous ones so grown. 
For various reasons, therefore, both practical and scientific, it 
seemed very desirable that the subject should be further investi- 
gated, both here and elsewhere. The experiments at Rothamsted 
have, accordingly, been continued up to the present time, and 
they are still in progress. 
Our first report, to which we have been referring, gave the 
results of the first three seasons (1856, 1857, and 1858), relating 
to three divisions of the subject, namely — the produce of hay 
per acre, the produce of constituents per acre, and the chemical 
composition of the hay — and on these points we have now on 
hand the accumulated results of four more seasons. The results 
formerly given on the remaining branch of the subject — the 
description of plants developed hj the different manures — related to 
the produce of the third season only, 1858 ; and the further details 
obtained on this head have reference to the produce of the 
seventh season, 18G2. It is to these that it is proposed to confine 
attention on the present occasion, presenting only such an outline 
of the voluminous records as will bring to view the points of 
most interest to the readers of an Agricultural Journal. 
Method of Experimenting. 
Taking advantage of the experience gained -in some attempts 
to separate and determine the proportion of the different plants, 
in carefully averaged and weighed samples of the produce in the 
previous year (1857), the produce of 1858 had been separated 
into — (1) Graminaceous herbage, stems bearing flower or seed ; 
(2) Graminaceous herbage, detached leaves and indeterminate 
stems ; (3) Leguminous herbage ; (4) Miscellaneous herbage, 
chiefly weeds. The components classified under these heads gave 
from 14 to 23 different descriptions of herbage ; and, no doubt, the 
results, so far as they went, clearly and truthfully indicated the 
characteristic and comparative distribution of plants on the dif- 
ferent plots. But as-there remained, in the separations in question, 
an amount equal in several cases to a fourth, and in one to more 
than a half of the whole produce, to be set down as Grami- 
naceous herbage in " detached leaves and indeterminate stems," to 
the components of which the specific names could not with any 
confidence be given, it seemed desirable, in again taking up the 
subject, to follow it out in considerably more of detail. Accord- 
ingly, in the separations recently made, of the produce of 1802, 
