628 FLORA OF BERKSHIRE 



a long one, and it is to be hoped that it will not he enlarged in the 

 immediate future. 



Mr. H. C. Watson, in the first edition of Topographical Botany, vol. ii. 

 pp. 665-710, gives a comital census of British plants which shows in 

 a tabular form their comparative distribution. It must be borne in 

 mind that the census numbers there given are now much too small, as 

 many additions have been made since the publication of that work. 

 Adopting the list of species there given, with the specific limitations 

 as made by Mr. Watson, we find that — • 



Of the 368 species which in that work are stated to be found in from 

 80 to no counties and vice-counties of Great Britain, all occur in 

 Berkshire. 



Of the 127 species found in from seventy to eighty counties, two 

 inland species, Sparganium natans and Eriophonim vaginatum, are not 

 recorded for Berkshire, but may possibly be found there. 



Of the 117 plants recorded as occurring in from sixty to seventy 

 counties, Berkshire has 108. The four inland species which are 

 missing are Etnpetrmn nigrum, Cystopteris fragilis, Polypodium Bryopteris 

 {Phegopieris Bryopteris^, and Chrysosplenium alternifolium ; the two latter 

 may yet be found. The five maritime species are not likely to occur. 



Of the 103 sjDecies which are recorded from fifty to sixty counties, 

 Berkshire has eighty-one. Eleven of the missing species are maritime. 

 The nine inland species, not recorded for the county on recent or trust- 

 worthy authority, are Vaccinium Oxycoccos {Oxycoccus qiiadripetala), which 

 may possibly be found in the bogs of the southern part of Berkshire, 

 Viola lutea, Thalidrum minus, Trollius, Myrrhis oclorata, Geranium sanXjuineum, 

 Caynpanula latifolia, Potamogeton heterophyllus (P. gramineum), the last of 

 which may be found in some of the large sheets of ornamental water 

 which occur in the county, Prunus Padus, and Vaccinium Vitis-idaea. Of 

 these species, Trollius, Viola lutea, Prunus Padus, and Vaccinium Vitis-idaea 

 are northern plants or fond of mountainous districts. Myrrhis, a, rather 

 doubtful native, is also a plant found more frequently in northern 

 Britain, and Campanula latifolia in southern England is always very 

 local. 



Of the 106 species stated to occur in from forty to fifty counties, 

 Berkshire has seventy-eight. Of those missing, thirteen are maritime 

 species, one of them, Sclerochloa {Panicularia) distans, being occasionally 

 found inland. Five belong to northern species which do not reach so 

 far south as Berkshire, while Eubus saxatilis, Saxi/raga hijpnoides, and Lyco- 

 podium alpinum belong to the Scottish group, which extends to the south 

 of England in mountainous or hilly districts, although the Lycopodium 

 has been found in Hampshire. Habenaria albida may possibly be dis- 

 covered since it is found on the South Downs, but Hymenophyllum uni- 

 latercde is not likely to occur. Some of the remaining four species. 



