THE SKOMER VOLE
Evotomys her cynicus skomerensis, sub-spec. nov.
Evotomys skomerensis, Barrett-Hamilton, ‘ Proc. Roy. Irish Acad.’ vol. xxiv., sect. B, art 4,
PP- 3I5- 3I9 (1903)-
Characters.— I cannot do better than quote Captain Barrett-Hamilton’s description
of this animal, which he regards as a species but which I consider
a sub-species: ‘ Size large; skull of adults about 25 mm. in greatest length;
total length averaging about 165 mm.; hind foot averaging 18 mm.; ratio of
tail vertebrae to total length 3 3 ; skulls strong (for Evotomys), angular, and ridged
for muscular attachment; the zygomata rather heavy. Colour deep and moderately
bright. Skull of the same type as that of E . nageri, with which it agrees in
size, angular appearance, and general massiveness, but is, on the average, slightly
smaller.’
The skull of an adult male presents the following dimensions (in mm.):
Greatest length 2 5 ; basilar length 22-5; palatal length 12 ; length of palatal
foramina 4/5; zygomatic breadth 14 ; breadth of brain-case above zygomata 1 1 75»
length of molar series (both upper and lower) 6 ; length of nasals along middle
line 8.
Colour.—Above between bright ‘ cinnamon-rufous ’ and ‘ madder-brown, the
general appearance being due to the sub-terminal bands of the hairs, about 2 mm.
in breadth. The hidden (and major) portion of these hairs is ‘ slate-black’ and
the tips black, face, sides of head, and flanks becoming gradually deficient in
rufous, and running through light ‘ hazel ’ or ‘ vinaceous-cinnamon ’ to a dull
greyish buff. Rump and upper side of the sharply bi-coloured tail ‘ mummy-
brown.’ Under side of body and tail, with the legs and feet, white (the hidden
portions of the hairs again were ‘ slate-black’), usually with a very perceptible
yellowish wash. The line of demarcation between the colours of the upper and
under surfaces moderately defined. Ears nearly naked externally, internally
covered with light ‘ cinnamon-rufous’ hairs. The dimensions of twelve specimens
the writer gives as follows: