VI PREFACE. 



The plates are not placed, as in " the Grasses of Scotland," at the 

 end of the work, but, for greater ease of reference, opposite to the de- 

 scriptions to which they relate. 



No pains have been spared to make the arrangement of the Tribes 

 and Genera as practically useful as possible, which has led to some 

 variations on the groups employed in " the Grasses of Scotland." 



With the same purpose of rendering the work as practically use- 

 ful as possible, I have introduced a few tables, which I hope may 

 prove of service in facilitating the progress of the student in this dif- 

 ficult department of botany. The first table exhibits the Grasses of 

 the United Kingdom arranged according to their time of flowering 

 from the first week of April to the third week of August. In a sepa- 

 rate column of the same table is indicated the week of the summer 

 and autumn months in which the seeds ripen, and in the remaining 

 columns are shown the habitat as peculiar to one or more of the di- 

 visions of the United Kingdom, or common to England, Ireland, or 

 Scotland, also the page where each grass is described, and the num- 

 ber of the plate where it is figured. 



The remaining tables are of less interest to the botanist, 'being 

 drawn from authorities on agriculture, and designed to afford to the 

 cultivator some hints of a general kind, under different circumstances, 

 for the choice and management of grasses. 



In conclusion I have only to add, that, to obviate misunderstand- 

 ing hereafter as to the species and varieties, I shall deposit with the 

 Linnean Society of London a specimen of the original grass plants 

 employed in the descriptions and figures throughout the entire work. 



Edinburgh, 

 March \st 1845. 



