20 
compared with that of another member who has chosen a different 
plan of dividing the county; and, if possible, it would be very 
desirable for the society to adopt a definite division as the basis 
of its local lists. 
Now, there are two w'ays of making such a division of any given 
space. The first and best, where it can be used, is to take 
advantage of natural boundaries, such as ranges of hills or rivers, 
which may make an actual difference of position, or of condition in 
the portions divided. The second is to make a purely arbitrary or 
artificial division, which shall merely map out the area into 
convenient districts, with as much regard to difference of character 
in those districts as may be attainable. 
The first of these two ways is unfortunately impossible in our 
own county — there are no great rivers or leading lines of hills that 
can be taken advantage of for its division, and we are of necessity 
obliged to fall back upon purely arbitrary divisions. 
The system of division which I propose that the society should 
adopt was originated by the Eev. George Munford, in his list of 
plants found in Norfolk, published in Whites Directory. He thus 
describes it : — “ To mark the distribution of species throughout 
the county I have divided it into four parts, and shall briefly 
mention the prevailing strata of each part as we proceed. 
“ First. — The eastern division (marked E in the map)* whose 
western side has for its boundary an imaginary line running north 
and south from Cromer to a little east of Harleston. This division 
contains the alluvium of the valleys of the Yare, the Bure, and 
the Waveney ; the blue clay which occupies the higher ground of 
the same valleys, next to which we meet with the larger part of 
the crag formation, and then a small portion of the upper chalk at 
the south-western corner of the division. 
“ Second. — The central division, separated into northern central 
(marked N.C. in the map) ; and Third, southern central (marked 
S.C. in the map) by an imaginary line running east and west from 
Norwich to Swaffham, both having for their western boundary 
another imaginary line, passing north and south from Brancaster to 
two or three miles west of Thetford. These divisions, with the 
exception of the north-east corner, which is crag, lie entirely on 
the upper and medial chalk formations. 
* Tlie map referred to was produced at the meeting. 
