mEFACE. xi 



gone entirely outside these limits whenever I have found 

 books not enumerated by Pritzel; those, therefore, who only 

 require a supplement to the Thesaurus will find it in this 

 volume, whilst the majority of readers will be glad of the 

 sj-'stematic arrangement. 



I have mentioned Pritzel' s Thesaurus as my chief source of 

 information, and have given expression to my warm apprecia- 

 tion of the work, in the article already referred to ; in addition 

 to this, I have searched the libraries of the Royal Herbarium, 

 Kew; the Linnean Society, including the collection of Linnaeus 

 himself ; the National Herbarium, British Museum, now re- 

 moved to South Kensington ; the Royal Microscopical Society ; 

 the Eanksian Tracts, numbering 720 volumes ; and the Lindley 

 Library. I have also diligently made use of the private stores 

 of many friends, and hunted up works named on title-pages, 

 in footnotes, in quotations, and in advertisements. I have 

 worked through the half-yearly parts of the Bihliotheca 

 Historico-naiuralis from its commencement in 1862 to the first 

 Heft of 1880, which reached me a few days before the printing 

 of the Addenda ; the various issues in this country of Bent's 

 Monthly Literary Advertiser, the JBooIcseller, and the Publishers' 

 Circular. Catalogues of other libraries and booksellers have 

 been carefully gone through, and the arduous task of com- 

 paring the titles so obtained, either with the books themselves, 

 or trustworthy authority, has been chiefly performed at the 

 British Museum ; there for many months I have made daily 

 use of such helps as Kayser, Heinsius, Lorenz, Querard, and 

 other bibliographical authorities. I have not attempted a 

 systematic overhauling of the more than 2200 volumes of the 

 Museum Catalogue, for this reason, that the results would 

 hardly be proportionate to the formidable task, the National 



