4 INTRODUCTION. 
Severn. If other names were already in familiar use and suffi- 
ciently applicable, those customary names have been retained im 
preference ; as in the case of North or South Wales, or Highlands 
and Lowlands of Scotland. 
In order to render these Provinces suitable for phyto-geogra- 
phical comparisons among themselves, it was sought to give to 
each a considerable portion of coast line; as otherwise maritime 
plants in some of them, and not in others, would have rendered 
their local floras less comparable. But the inland province of 
Severn was unavoidably left with a coast line of less extent than 
elsewhere. For convenience of geographical nomenclature it was 
deemed better to keep the twelve counties of Wales to themselves ; 
and to have included all Somerset with the Severn counties, more 
strictly so designated, would have intruded their province too far 
into that of the Peninsula. The existing conditions of botanical 
knowledge and records, at the date of 1840—5, likewise in some 
degree affected the provincial boundaries, more especially those of 
the Highland provinces. The counties were so grouped that the 
then existing records should furnish a tolerably full list of the 
species for each group. Otherwise, it would have been preferable 
to group the Highland counties into four provinces instead of 
three only ; also, to keep the Western isles of Scotland, Ebudes 
and Hebrides, united together as one province, apart from the two 
sub-groups of Northern isles, Orkney and Shetland. But the 
botanical data on record a quarter century ago, though much 
increased by the present writer’s own manuscript notes, were still 
too incomplete and imperfect to allow a compilation of local Floras 
for six instead of four Highland and Insular provinces. By a 
subsequently adopted arrangement, presently to be explained, the 
same counties and isles can now be treated as ten sub-groups, 
instead of four chief groups, in cases where the more numerous 
partitions are likely to prove more useful. 
Before proceeding to explain the other divisions and sub- 
divisions of Britain, more numerous than these eighteen pro- 
vinces, it seems advisable to present a list of the counties 
enumerated under their respective provinces ; this first grouping 
