XX 11 PR E 1 A C E. 



botany of my Dative country perpetually under con- 

 sideration in the progress of the English Botany and 

 Flora Britanmea ; and this same subject having en- 

 gaged the attention of numerous coadjutors, espe- 

 cially among those members of the Linnsean Society 

 who have contributed to enrich its Transactions ; I 

 am aware of so great a progress in our general stock 

 of knowledge, that a Flora of Britain, far from being 

 necessarily a compilation, or a translation, must now 

 be a new and original work. The books just men- 

 tioned may, indeed, form the basis of such an un- 

 dertaking; but the science of Botany, through their 

 means, has been progressive in an eminent degree, 

 for twenty years past, and the accession of new-dis- 

 covered species will be found no less considerable in 

 that space of time, than the elucidation of those pre- 

 viously known. Two natural orders of plants in par- 

 ticular occur, in the present volumes, under entirely 

 new points of view; the Linnaean Calamaria> chiefly 

 comprehended in the Triandria Monogynia, and the 

 Umbellate?, in Pentandria Digynia. The genera of 

 the former had never been well defined, till Mr. 

 Brown, in his Prodromus of the Flora of New Hol- 

 land, undertook this difficult task. His labours have 

 generally been my guide, and I have ventured to dif- 

 fer from this, great botanist chiefly in one particular. 

 He admits, as an essential generic distinction, the 

 absence or presence of certain bristles under the 

 seed in the Calamariaz. The observation of nature, 

 in several instances, but especially in Scirpus cari- 

 cinus and riifus, pp. 58, 59, has taught me, beyond 

 a doubt, that such bristles ought to have no place 

 in the generic characters, though they here distin- 



