154 
Effects of different Manures on the 
although Trifollum and Lathyrus were less frequent on the 
farmyard-manure than on the unmanured plot, thev were on the 
other hand more luxuriant. 
The ^liscellaneous or weedy plant most prominently developed 
by farmyard-manure was the Rumex acetosa, or sorrel dock, 
which amounted to rather more than 10 per cent, of the sample 
examined ; though, from the notes taken on the ground, it is 
concluded that the sample perhaps included a somewhat undue 
proportion. According to the notes, Carum Carui w as by far the 
most frequently occurring weed. Ranunculus (acris and bulbo- 
sus), and Achilla^a millefolium were also each very frequent ; 
and Plantago lanceolata w as more so than in most of the crops 
of equal bulk. Besides those mentioned, scarcely any other 
weedy plants occurred ; there being a large total percentage of 
Miscellaneous herbage, but referable to comparatively few species, 
and it was the frequency rather than the luxuriance of these that 
contributed to the large amount. 
Effects of Farmyard-manure and Ammonia-Salts. 
As already alluded to, the combination of farmyard-manure 
and ammonia-salts, like farmyard-manure alone, very strikingly 
developed the Poa trivialis, and to a considerable extent the 
Bromus mollis also. The chief distinction is, that the ammonia- 
salts used in conjunction with a manure supplying a large 
amount of mineral matter, strikingly increases the growth of the 
Dactylis glomerata, apparently at the expense of the Miscellaneous 
herbage, of which there were but very few species, and but a 
small amount, whilst the proportion of total Graminaceous herb- 
age was considerably increased. In other respects, the produce 
was very similar in its Graminaceous components to that by farm- 
yard-manure alone ; there being, in the two cases, besides the 
grasses which have been specially noticed, pretty equal propor- 
tions of most of those occurring on the unmanured plot. Holcus 
lanatus was, however, rather more plentiful and luxuriant where 
the ammonia-salts were used. 
Under the influence of ammonia-salts in conjunction with 
farmyard-manure all the elements of Leguminous herbage were 
almost as completely excluded as when ammonia-salts were used 
alone. 
The number of species of Miscellaneous plants was unusually, 
small under the conditions of manuring now in question ; and 
the proportion in the produce of such herljage was also small. 
As in the case of farmvard-manure alone, Rumex acetosa was the 
most prominent weed. Judging from the notes and figures together, 
Carum w as probably next in order of prevalence ; and alter it 
