136 
A. E. GIBBS— HEKTEORDSHIRE MAMMALIA. 
The bank or red vole is very partial to sheltered banks covered 
with ivy and other vegetation, and its runs can he traced in the 
meadow-grass. It builds a loosely-constructed nest amongst herbage, 
the one exhibited having been found in some nettles, slightly raised 
above the surface of the ground, and I have had it mounted for 
the Museum. The voles themselves were mostly taken in an 
ordinary penny trap. 
The common vole ( Microtus agrestis ), of which I have also 
brought specimens for comparison, is nearly allied to the bank-vole, 
from which it may be distinguished by its shorter tail and its 
browner colour. We have specimens at the Museum from St. Albans 
and Symond’s Hyde. This species is a most destructive one, and 
as it multiplies at a very rapid rate when its natural enemies 
the hawks, owls, weasels, and other birds and beasts of prey are 
exterminated, it sometimes does an immense amount of damage 
to growing crops and young trees. Its best friend is consequently 
said to be the keeper who kills those predatory creatures. 
The wood-mouse (Mus sylvaticus ) is another species which was 
common in my grounds in 1903, and of which we trapped a number 
of specimens. I exhibit a group which Mr. Bullen, our taxidermist, 
has cleverly set up for the Museum. 
Besides the albino specimen of the common shrew to which 
I have already referred, I have brought for inspection Hertfordshire 
specimens of our two other shrews, the water-shrew ( Crossopus 
fodiens ) and the lesser shrew ( Sorex minutus), the latter a not very 
common animal, I think. It has the distinction of being our 
smallest British mammal. 
Of the 28 species .of Mammalia which have been recorded as 
occurring in Hertfordshire, my own grounds, only four or five 
acres in extent, have yielded eleven, viz. : — 
Long-eared Bat (Plecotus auritus). 
Mole (Talpa europcea). 
Weasel (Mustela vulgaris). 
Squirrel (Sciurus vulgaris). 
Dormouse (Muscardinus 
avellanarius). 
Wood-Mouse (Mus sylvaticus). 
House-Mouse [M. musculus). 
Brown-Bat (M. decumanus). 
Water-Yole (Arvicola amphibia). 
Bank-Yole (A. agrestis). 
Babbit (Lepus cuniculus). 
