THE BRITISH WOODLICE. 103
it rolls up. It is interesting to compare this species with Cylisticus
convexus. The surface of the body is smooth, and its colour is a
delicate brownish grey with more or less distinct rows of darker
markings.
BRITISH LOCALITIES :—
England : Maldon ; (W.M.W. from R.M.): Bluebell Hill,
Maidstone (W.M.W.); Clifton, banks of the Avon; (W.M.W.
from J.T.C. 1900) : Leigh Woods, Clifton; Tunbridge Wells;
South Devon; (Stebbing in 49); Cheddar Cliffs, Somerset;
(Norman, 49).
FOREIGN DISTRIBUTION :—
Europe: Fiance ; (28) ; Spain; (12): Italy ; (23).
Armadillidium vulgare Latreille. Plate XXIII.
1804 Armadillo vulgaris Latreille (37), p. 48.
1804 Armadillo variegatus Latreille (37).
1853 Armadillo ater Schnitzler (65), p. 48.
1816 Armadillo maculatus Risso (56), p. 158.
1818 Armadillo pillularis Say (621, p. 432.
1825 Armadillo pustulosus Dermarest (11), p. 323, pl. XLIX.
l830-4 Armadillidium commutatum Brandt and Ratzeburg (4), p. 81, pl.
XIII.. fig., 123.
1833 Armadillidium zenckeri Brandt (3), p. 185.
1830 Armadillo trivialis Koch (34), part 28, pl. XIV.
1898 Armadillidium vulgare Sars (59), p. 189, pl, LXXXII.
The common pill Woodlouse is Armadillidium vulgare. Its
frontal lobe is not large, though it is broad, while its margin
where it joins the head is rounded and slightly
recurved. The proximal joint of the flagellum
is somewhat the shorter and the two together,
as in Armadillidium nasatum, are of about the
same length as the last joint of the peduncle.
The telson has the form of a triangle with
the angles truncated and is about as long as it
is broad at the base. The outer divisions of
the tail appendages are considerably broader
than they are long.
The species can roll itself up into a very
perfect sphere, and when it assumes this form
its antennas are hidden beneath the much
expanded lateral plates of the first thoracic
segment.
The body is smooth, shiny, and strongly
arched. Its colour varies very considerably,
generally it is of a slaty-grey, but yellow mark-
ings are often present to a greater or less extent. In a specimen
before us (from Bluebell Hill, Maidstone) the head is of a