125 
NOTES ON THE "CENSUS OP SCOTTISH 
MOLLUSCA." 
F. Buchanan White, M.D., F.L.S., F.E.S. 
MR. T. SCOTT'S remarks (in his valuable paper on the 
Scottish species of Vertigo) upon the Fifeshire locality 
for Vertigo minutissima {Scot. Nat., April, 189 1, p. 53) rather tend 
to confirm the impression which a perusal of Mr. Roebuck's 
" Census " left upon me. That " Census " is a very valuable and 
interesting contribution to our knowledge of the distribution in 
Scotland of the Land and Fresh-water Mollusca, but I think that 
the author has not made it quite clear that it is a ^' Census," not 
of the recorded distribution, but of specimens received as vouchers. 
Hence, in the tabulated statement all the old records are neces- 
sarily ignored, and, if it alone is consulted, a very erroneous im- 
pression of the actual work which has been done amongst the 
Scottish Mollusca will be conveyed. In addition to this, doubt 
seems to be cast upon the genuineness of previous records, although 
I do not believe that Mr. Roebuck intended to do this. In con- 
nection with the " Census," I am sorry that Mr. Roebuck did not 
see his way to indicate the distribution in the faunal areas or dis- 
tricts, that is, of the natural divisions instead of the artificial 
divisions formed by the counties. Since the whole world is now 
divided into accepted faunistic areas, and the local faunistic areas 
of Scotland are coming more and more into use (See Rev. H. A. ^ 
Macpherson's paper, p. 60), it is retrogression to go back to the 
artificial boundaries of the counties. Mr. Roebuck has two or 
three objections I think (his paper is not now beside me) to the 
use of the natural areas. One is that these are too large. In one 
case — that of " Moray" — I have for some time been of his opinion, 
but when I first divided Scotland into faunistic areas {Scot. A^at.. 
vol. I., p. 161, 1872), I did not see my way clearly to sub-divide 
it. Another objection is that it is difficult to divide England intf) 
similar areas. This difficulty is, I think, more imaginary than 
real. A year or two ago I found that England could be divided 
into twelve great divisions. Some of these would require to be 
sub-divided, but that is a matter for English naturalists to settle 
amongst themselves. It will have to be done some day, so the 
