1326 
MESSRS. J. B. LAWES, J. H. GILBERT, AND M. T. MASTERS, 
according to the amount, the description, and the combination in which the nitrogen is 
employed. The characteristic tendency of the various mineral manures, on the other 
hand, is to favour consolidation or maturation rather than luxuriance, and, hence, 
when used alone, the competition becomes less severe, and a larger number of species 
is enabled to maintain a place. 
The lines in the table showing the percentages of the total Graminese, total Legumi- 
nosae, and total Miscellaneae, exhibit such extremely wide ranges in their proportion to 
one another in the four complete separation-years, that it is difficult from the figures 
there given to form a definite conclusion as to the tendency of either group to increase 
or diminish in relative proportion. Calling to our aid the results of the partial sepa¬ 
rations made in. several intermediate and succeeding years, it must be concluded that 
the grasses have increased in their proportion during the later years, whilst the 
Leguminosse have not sustained the tendency to increase so prominently in the later 
as in the earlier years. It may also be said of the Miscellaneae that the tendency 
with them is to decline in proportion. In actual amount per acre, too, the grasses 
have of late years increased, and the Leguminosse and the Miscellaneae diminished. 
Without manure, on the other hand, though the actual quantities per acre are much 
less than with the mineral manure, the grasses have diminished very considerably, the 
Leguminosae have even increased, but the Miscellaneae have diminished even in greater 
degree than with the mineral manure. 
Whilst referring to the relation to one another of our three main groups, some 
reference should be made to the characters of the second crops in this respect. The 
indication is that in the second crops the percentage of Graminese is generally higher, 
and that of the Leguminosae and Miscellaneae lower ; and this is especially the case on 
the mixed mineral manure plot now under consideration. 
Among the grasses, Festuca ovina is by far the most prominent species, and is 
increasing ; but it is, nevertheless, in by no means such excessive proportion, or amount, 
as on the plots with an excess of nitrogenous manure. Agrostis vulgaris and Holcus 
lanatus are also prominent, and, upon the whole, increasing ; though the latter shows 
considerable fluctuation, according to season. Taking the average of the four com¬ 
plete separation-years, these three most prominent grasses yield collectively only about 
one-third of the total herbage ; and, consistently with the character of comparatively 
little forced luxuriance of individual species, a considerable number of other grasses 
contributes a fair proportion to the produce. The most prominent of these, on the 
average, though declining, is Avena pubescens , then A. flavescens ; next come Dactylis 
glomerata, Poa trivialis, and Anthoxanthum odoratum, in about equal amounts ; then 
Lolium perenne , and, in smaller quantities, but still apparently maintaining some 
position, come Poa pratensis, Avena elatior, and Alopecurus pratensis. 
The final column in the table further indicates the general character of the change 
induced by the mixed mineral manure as compared with the produce without manure. 
It is seen that, of Alopecurus pratensis, Lolium perenne, Anthoxanthum odoratum, 
