on Permanent Meadow Land. 
265 
amount of this plant were considerably greater than where the 
smaller amount was employed with the mineral manures. Con- 
sistently with this effect of ammoniacal salts, the proportion of 
the Milfoil was very much increased by the addition of these salts 
to farm-yard manure ; and it was the greatest — in fact, then nearly 
three times as great as without manure — where the ammoniacal 
salts were used alone. 
If the characters of the Milfoil as sheep-food be such as above- 
described, it need not perhaps be much regretted that its 
growth seems to be favoured by nitrogenous manures. 
4. — JRumcx acetosa — Sheep' s-sorrel or Dock. 
This plant is undoubtedly objectionable. Unfortunately, how- 
ever, it, as well as the Milfoil or Yarrow, was found in the pro- 
duce of every plot ; and, like the latter, it was increased in its 
growth by the use of ammoniacal salts. It was more or less 
increased by these salts in whatever combination they were 
employed. Farm-yard manure alone also notably increased the 
proportion of the Dock in the produce ; but farm-yard manure 
and ammoniacal salts together increased it still more. With 
the latter combination the Dock amounted to more than 3 per 
cent, of the produce. As this obnoxious plant seems to be 
favoured in its growth by manuring, its expulsion must be 
attained by other means. 
The remaining five plants that \,'ere detected in the samples 
are, without doubt, useless, if not obnoxious. They were each 
found, however, only on a few of the plots, and generally in but 
insignificant proportion. 
5. — Silene, or Catch-Jly, 
was found in the unmanured produce only, and there to the 
extent of little more than ^ per cent. 
6. — Ranunculus — Crow-foot (various species). 
These plants were found in small quantity in the produce from 
the unmanured plot ; in larger proportion in that grown by 
ammoniacal salts alone ; and in larger proportion still on the 
two plots with farm-yard manure. Their growth was, how- 
ever, very much discouraged by the most productive artificial 
manures. 
7. — Lazula Campestris — Field Wood-rush. 
This rush was found only in the sample from the unmanured 
land, and there in very insignificant amount. 
