A HISTORY OF NORFOLK Cambridgeshire has, all of which are absent from Norfolk and Suffolk ; Viola stagninay Carum Bulbocastanum, Valeriana Auricula, and Ajuga Chamcepitys. Cambridgeshire and Norfolk have the following, which do not occur in Suffolk, Rcemeria hybrida. Campanula patula, Narthecium Ossifra- gum and Phleum asperum. Cambridgeshire and Suffolk have the following which are absent from Norfolk, Vicia gracilis, Myriophyllum alternijiorum, Caucalis latifolia, Serratula tinctoria, Senecio campestris, Orobanche Picridis, Veronica spicata and Ophrys aranifera. Lastly, Norfolk and Suffolk have the following which are absent from Cambridgeshire, Diplotaxis tenuifolia, Silene conica, Dianthus armeria, Holosteum umbellatum, Scleranthus perennis, Trigonella purpurascens, Tillaa muscosa, Chrysosplenium oppositifolium and C. alternifolium, Orobanche carulea. Verba scum pulverulentum, Veronica verna and V. triphyllos, Scutellaria minor, Tulipa syhestris, Gagea lutea, Lastrea cristata and L. uliginosa and Ceterach qfficinarum. The genus Gentiana is curiously distributed among the three counties. Norfolk has four species : G. Amarella, G. Pneumonanthe, G. campestris and G. baltica ; Suffolk but three, G. baltica not being differentiated there at present ; but Cambridgeshire has only one species : G. Amarella. The writer has been so fortunate as to obtain the help of the following specialists who have each contributed an article. The Rev. G. R. Bullock-Webster, on Characeae ; C. B. Plowright, M.D,, on Fungi ; H. N. Dixon, on Mosses ; and the Rev. J. Crombie, on Lichens. His special and most grateful thanks are due to Mr. Arthur Bennett for correcting the list of Naiadaceae and to the Rev. E. F. Linton for allowing him the use of his ' Norfolk Notes ' on Rubi and Rosa, also to the Norfolk and Norwich Naturalists' Society for allowing him free use of their Transactions. He also desires to record his in- debtedness and thanks to The Rt. Hon. Lord Walsingham, F.R.S. ; Messrs. E. G. Baker, of the Museum of Natural History, South Kensington ; E. M. Holmes, of the Pharmaceutical Society's Museum ; R. H. Yapp, of the Cambridge University Herbarium ; E. A. Atmore, of the Museum, Kings Lynn ; and the Rev. E. K. Kerslake, for assistance given both by correspondence and personally. The principal authorities to be consulted for localities and details of Norfolk Botany are, Withering, Arrangement of British Plants, 4th ed. 1801 ; Sir J. E. Smith, English Botany, ist ed. 1790-18 14 and English Flora, 1 824-1 828 ; English Botany, 3rd ed., edited by J. T. Boswell Syme, 1863 ; Transactions of the Norfolk and Norwich Naturalists^ Society (various years) ; lists of Flora of Norfolk in White's History, 3rd ed. 1864, by the Rev. G. Munford, and in Mason's History, 1884; The Rev. Kirby Trimmer, Flora of Norfolk and Supplement, n.d. ; H. C. Wat- son, Topographical Botany, 2nd ed. 1883; and the Rev. E. F. Linton, ' Norfolk Notes,' Journal of Botany, June and July, 1900. 44