lxvi 



ROYAL HORTICULTURAL SOCIETY. 



I may mention, however, that the facts which would supply the 

 material for the consideration of the Committee have been pro- 

 vided as follows : — ■ 



In the series of investigations conducted by Mr. Lawes and 

 myself at Bothamstead, a portion of his park, which has probably 

 been under grass for centuries, has been divided into plots, each of 

 which has been treated in the same way as to manure, year after 

 year, for more than a dozen years — there being nearly twenty 

 plots, and nearly as many manurial conditions. It was soon found 

 that the relative predominance of various species of the complex 

 herbage rapidly changed, according to the description of manure 

 employed; on three occasions carefully selected samples have been 

 submitted to what may be called botanical analysis. The produce 

 of 1867 was so treated, and the separations have occupied several 

 pairs of hands from the time of cutting last year until only a few 

 weeks ago. 



As a general result, it may be stated that whilst the unmanured 

 produce is found to comprise about fifty species, that from some of 

 the plots includes less than half that number ; and not only may 

 the plants of certain orders be almost excluded under certain 

 conditions, and most strikingly increased under others, but indi- 

 vidual species, even among the grasses themselves, are affected in 

 no less a degree. It will be seen that the results afford most 

 striking and interesting illustrations of the " struggle for exist- 

 ence " among plants. It is our intention to follow up the inves- 

 tigation in the same manner as hitherto ; but we cannot but feel 

 very strongly that there is a point beyond which we, as chemists 

 and agriculturists, cannot hope to carry the subject, and that the 

 results open up a very fruitful field for the study of the botanist 

 and vegetable physiologist, and might prove of much interest, and 

 deserve much elucidation, if considered from so many points of 

 view as might suggest themselves in discussion by a body repre- 

 senting so many branches of science as the Scientific Committee. 



I will bring with me, on Tuesday, some tabular summaries of 

 the results 3 but I may mention that the plots themselves are just 

 now in a very interesting condition for inspection, and Mr. Lawes 

 begs me to add he will have much pleasure in sending an invita- 

 tion to each Member of the Committee, should it be convenient to 

 find a day for a visit to Kothamstead. Yours truly, 



J. H. Gilbert. 



