176 Mr. R. 8. Bagnall on some 
colour as the body, tinged with dull rufous only on the 
forearm above the knees ; hind legs similar, but with rufous 
tinge on back of legs above hocks and between the hocks 
and fetlocks ; superciliary streaks and sides of face pale 
greyish brown ; underparts pale greyish brown ; throat and 
inside thighs white. 
Hab. Chirinda Forest, Melsetter, Rhodesia. 
Type. Adult female skin, B.M. no. 8.7.19.36. Collected 
by C. P. M. Surgmerton, Esq. 
The writer considers these characters of slight variations 
of colour and size to be of local and family value only, 
always likely to arise where animals by environment 
and habit are confined in widely-separated patches of 
country. Such as these little forest duikers probably never 
move more than a few miles from their birth-place, and 
keep within the limits of restricted and isolated belts or 
patches of dense bush or forest, where conditions are scarcely 
affected by change of season, and the plants on which they 
live are always present in abundance. 
These conditions would encourage in-and-in breeding, pro- 
ducing an infinite variety of races in which small changes 
of size and colour would tend to become fixed characters. | 
Possibly in the great forest-tracts of Central Africa a 
greater individual variation would be apparent, but south of 
that region there are no great areas of forest, but only 
isolated belts and patches occurring here and there along 
the courses of rivers, or in mountain-ranges, or on the coast, 
at wide intervals, each possessing a local race stamped with 
its individual trait. 
XVI.—On some new and rare British Diplopods. 
By Ricuarp 8. BAGNALL, F.R.S.E., F.L.S. 
Iv is desirable to make the following records, Leptoiulus 
belgicus and Mastigonodesmus boncit being additions to the 
British fauna, whilst Zsobates sp. would seem to indicate, 
from observations in the field, a new species. 
I regret that, living in hotels, away from my literature, 
specimens, and appliances, it is impossible to make any useful 
descriptions or remarks. 
Leptotulus belgicus (Latz.). 
A graceful Julid, with a single white dorsal line and pale 
