THE BATTLE OF LIFE. 109 



miscellaneous weeds also small. These effects are greater 

 and more observable, the larger the quantity of ammonia, 

 though the effects are by no means doubled in intensity, 

 when the quantity of ammonia is doubled. The average 

 produce has been larger than that of the other plots. The 

 number of species has diminished, especially in the case of 

 miscellaneous plants. Where the ammonia was in relatively 

 slight proportions, Festuca ovina, Agrostis vulgaris, Avena 

 elatior, Holcus lanatus and Poa pratensis, are noted to have 

 been predominant, Poa trivialis, on the contrary, being 

 practically banished. The two first-named plants owe their 

 predominance not exclusively to the manure, for they thrive 

 luxuriantly under many other conditions. A similar remark 

 applies to Rumex Acetosa. On those plots where the 

 quantity of ammonia salts was doubled, Dactylis glomerata 

 for some years was in enormous preponderance, Agrostis vul- 

 garis, IIolns lanatus, Alopecurus pratensis and Avena elatior 

 have been also in large quantities. Briza media, Cynosurus 

 cristatus, Lolium perenne, Bromus mollis, all poor grasses, 

 except Lolium, have been discouraged by the ammonia. 

 Poa trivialis also has greatly diminished in proportion to 

 the quantity of P. pratensis. 



Among the miscellaneous plants, Kanunculacese, like 

 the Leguminosse, have been practically banished. Um- 

 belliferse have been almost expelled, Composite largely 

 diminished, Labiates greatly reduced ; Plantago lanceolata 

 is unrepresented, and even Eumex Acetosa considerably 

 diminished. As these or corresponding effects are gener- 

 ally observed where ammonia forms part of the manure 

 employed, and as they are enhanced when the quantity is 

 increased (though not in direct proportion), it would seem 

 that ammonia must be actually prejudicial to some plants. 



