_FOREIGN DISTRIBUTION:--_

_Europe_: France; (25): Spain; (15): Italy; (19): Norway; Sweden;

Denmark; Germany; (59).

_Africa_: Algeria; Tunis; Azores; (24).

_America_: Niagara; North America; (59).

=Trichoniscus vividus=, Koch. PLATE IV. (from a spirit specimen).

1840 _Itea vivida_ Koch (34), part 34, pl. IV.

1858 _Philougria vivida_ Kinahan (33), pp. 197 and 198, pl. XXIII.,

fig. 2.

1868 _Philougria vivida_ Bate and Westwood (1), Vol. II., pp. 458

and 459, figs.

This species is claret-brown in colour and under a lens it is seen

to be marbled with white, indeed in appearance it is much like

_Trichoniscus pusillus_ though twice the size. There are important

differences between the two species as regards the number of joints to

the flagellum. These vary from five to seven in _Trichoniscus vividus_

while in the other, as already pointed out, there are not more than

four. The body is practically speaking smooth for it bears only very

small tubercles, widely separated. In _Trichoniscus vividus_ the

antennæ lack the bristles which characterise those of the other species

in the genus. The species under consideration was discovered by Dr.

Kinahan in March, 1858, at Portlaw, Co. Waterford and is active even

amongst the snow.

[Illustration: FIG. 38.--FLAGELLUM AND LAST PEDUNCULAR JOINT OF THE

ANTENNA OF _Trichoniscus vividus_.]

_BRITISH LOCALITIES:--_

_Ireland_: Portlaw, Co. Waterford; (Kinahan, 33): Cappagh, Co.

Waterford; (Scharff, Irish Nat., Vol. IX., p. 158): Borris, Co.

Carlow; (Scharff, 64.)

_FOREIGN DISTRIBUTION:--_

_Europe_: Spain; (12).

=Trichoniscus roseus= Koch. PLATE V.

1838 _Itea rosea_ Koch (34), part 122, pl. XVI.

1858 _Philougria rosea_ Kinahan (33), pp. 197 and 199, pl. XXIII.,

fig. 3.

1858 _Philougria rosea_ Bate and Westwood (1), p. 460.

1898 _Trichoniscus roseus_ Sars (59), p. 163, pl. LXXIII., fig. 1.

The third British species of _Trichoniscus_ is of a deep pink colour

and has a light yellow stripe down the back (in some habitats the

animals are said to be quite white). Arranged in transverse rows upon

the body are large tubercles, each of which under strong magnification

will be found to end in a tiny hair. It is distinguished from

_Trichoniscus pusillus_ by the larger size of its body, which is

also comparatively broader, and from _Trichoniscus vividus_ by the

four joints of the flagellum of its antennæ which latter have strong

bristles upon them. In the former species there are five or more joints

to the flagellum and the antennæ, though hairy, lack the bristles.

_Trichoniscus roseus_ is to be looked for in old gardens.

[Illustration: FIG. 39.--FLAGELLUM AND LAST PEDUNCULAR JOINT OF THE

ANTENNA OF _Trichoniscus roseus_.]

_BRITISH LOCALITIES:--_

_England_: Warley; (W.M.W.): Maldon; (W.M.W. from R.M.): Stanmore;

Hanwell; Ealing; Wimbledon; (W.M.W.): Berkhamsted; Torquay;

(Norman, 49): Plymouth; (Bate and Westwood, 1 and B.M.,):

Grassendale, near Liverpool; (R.W.): Newtownards; (R.W., Irish

Nat, 1904, p. 260.)

_Scotland_: Tarbert; (Scot, 68).

_Ireland_: Dublin; Ballyfinder, Co. Down; (Scharff, 63):

Templeogue; Dundrum; Blackrock; Rathgar, Co. Dublin; Bray, Co.

Wicklow; (R.F.S.): Oakleigh; Kerry; (R.W.): Belfast; (Welch, Irish

Nat., 1896, p. 213.): At the grave of Josiah Welch (grandson of

John Knox), Castle Upton; Richhill, Co. Armagh; Castleconnell

Ferry; (R.W.): Glenade House, Co. Antrim; (R.W. from R. Ll.

Praeger).

_FOREIGN DISTRIBUTION:--_

_Europe_: France; (25): Spain; (12): Italy; (59): Denmark;

Germany; Holland; (39): Dalmatia; (18).

_Africa_: Algeria; Tunis; (24).

_Genus_--=TRICHONISCOIDES=, Sars, 1898 (59), p. 164.

_Abdomen narrow; eyes simple; (or wanting); flagellum, with four

joints._

The members of this genus are very much like those of _Trichoniscus_.

In the latter, however, the hinder legs are longer in proportion and

the eyes are compound.

=Trichoniscoides albidus= Budde-Lund. PLATE VI.

1879 _Trichoniscus albidus_ Budde-Lund (7) p. 9.

1898 _Trichoniscoides albidus_ Sars (59), p. 165, pl. LXXIII.,

fig. 2.

[Illustration: FIG. 40.--FLAGELLUM AND LAST PEDUNCULAR JOINT OF THE

ANTENNA OF _Trichoniscoides albidus_.]

We are able to include this species, as a specimen was found by Mr.

Webb at Eton Wick in the summer of 1899. It is one of a number of

species which the Rev. Canon Norman (49, p. 18) suggested as likely to

be British. It is the only representative of its genus, which does not

differ in any very important characters from the others in the family.

The narrow elongated body will serve to separate it from _Trichoniscus

vividus_ and _Trichoniscus roseus_, but on account of its size, which

is much the same as that of _Trichoniscus pusillus_ and the two British

species of _Haplophthalmus_, it will be advisable to give some further

points of distinction. From the first its white colour will serve

to differentiate it; the other two lack the narrow abdomen seen in

_Trichoniscoides albidus_. Moreover, not one of the three shows the

serrations on the side plates which characterise the species under

consideration. _Platyarthrus hoffmannseggii_ is small and white and

the edges of its side plates are toothed, but it is oval in shape,

possesses no eyes, and its stout antennæ have but a single joint to the

flagellum instead of four. On the Continent this species has been found

in rich soil.

_BRITISH LOCALITIES:--_

_England_: Eton; (Stebbing, 71a): Sunderland; (Brady, 50a).

_FOREIGN DISTRIBUTION:--_

_Europe_: France; Wimereux and Lyons, Forêt (25): Norway;

Denmark; (59).

_Genus_--=HAPLOPHTHALMUS= Schöbl, 1850 (66), p. 449.

_Abdomen broad (comparatively); eyes simple; flagellum with three

joints; back with longitudinal ridges._

The body of _Haplophthalmus_ is long in proportion to its width, but

there is no abrupt decrease in the breadth of the abdomen as seen in

_Trichoniscus_ and _Trichoniscoides_. The eyes are simple as in the

latter genus and the lateral lobes of the head are rather large, while

the side plates of the body are well separated.

=Haplophthalmus mengii= Zaddach. PLATE VII.

1844 _Itea mengii_ Zaddach (77), p. 16.

1860 _Haplophthalmus elegans_ Schöbl (66), p. 449.

1885 _Haplophthalmus mengii_ Budde-Lund (8), p. 250.

1898 _Haplophthalmus mengii_ Sars (59), p. 167, pl. LXXIV.,

fig. 1.

The Rev. Canon Norman discovered two specimens of this species in

Ireland in June, 1900 (50); in the previous year one of us (Mr. Webb)

found a single example at Eton Wick.

The main differences between the members of this genus and their allies

are set forth in the generic description and incidentally elsewhere, so

we shall content ourselves with giving the distinctive points of the

two British species. _Haplophthalmus mengii_ has a number of raised

longitudinal ribs on each segment of the thorax, the outer ridges being

somewhat broken. There are also two prominent ribs upon the third

segment of the abdomen.

[Illustration: FIG. 41.--FLAGELLUM AND LAST PEDUNCULAR JOINT OF THE

ANTENNA OF _Haplophthalmus mengii_.]

_BRITISH LOCALITIES:--_

_England_: Eton; (Stebbing, 71a): Sunderland; (Brady, 50a).

_Ireland_: Corcumroe Abbey; Co. Clare (Norman, 50).

_FOREIGN DISTRIBUTION:--_

_Europe_: France; (25): Norway; Prussia; Germany; Bohemia; (59).

=Haplophthalmus danicus= Budde-Lund. PLATE VIII.

1870 _Haplophthalmus elegans_ Budde-Lund (6), p. 228

(not _Haplophthalmus elegans_ Schöbl).

1879 _Haplophthalmus danicus_ Budde-Lund (7), p. 9.

1881 _Haplophthalmus mengii_ Weber (76), p. 192, pl. V., figs. 7-9

(not _Itea mengii_ Zaddach).

1885 _Haplophthalmus danicus_ Budde-Lund (8), p. 250.

1898 _Haplophthalmus danicus_ Sars (59), p. 168, pl. LXXIV., fig. 2.

This species was added to the British list by the Rev. Canon Norman

(49), who found a colony in his garden at Berkhamsted. It has rows of

tubercles on its thorax instead of ridges, and there are no ribs at all

upon the abdomen. The front of the head projects further comparatively

and forms a more acute point than in _Haplophthalmus mengii_ and it is

not so purely white in colour as the latter species.

[Illustration: FIG. 42.--FLAGELLUM AND LAST PEDUNCULAR JOINT OF THE

ANTENNA OF _Haplophthalmus danicus_.]

_BRITISH LOCALITIES:--_

_England_: Warley Place; (W.M.W. from Miss Willmott): Queen's

Cottage, Kew Gardens; Stanmore; Hanwell, garden at Odstock,

Bennett's Nurseries; (W.M.W.): Berkhamsted; (Norman, 49):

Sunderland; (Brady, 50a).

_FOREIGN DISTRIBUTION:--_

_Europe_: France; (25): Denmark; Holland; Germany; (Dollfus, Feu

de Jeun, Nat., April, 1896): Norway; (Sars, 59).

_Section_--=ONISCI.=

THE OUTER DIVISIONS OF THE TAIL APPENDAGES BROADER THAN THE INNER ONES.

_Family_-ONISCIDÆ.

=Tail appendages projecting when the animal is walking.=

(1.) Unable to roll up into a complete ball.

_Genus_-=ONISCUS= Linné 1746 (41), p. 360.

_Flagellum, with three joints; abdomen broad; head with lateral lobes._

The characters given above taken in conjunction with the size of the

animals will serve to distinguish the members of this genus.

=Oniscus asellus= Linné (The "Common Slater.") PLATE IX.

1761 _Oniscus asellus_ Linné (41), p. 500, No. 2058.

1792 _Oniscus murarius_ Cuvier (9), p. 22, pl. XXVI.

1838 _Oniscus fossor_ Koch (34), part 22, pl. XXII.

1868 _Oniscus asellus_ Bate and Westwood (1), p. 468.

1868 _Oniscus fossor_ Bate and Westwood (1), pp. 471-2.

1898 _Oniscus asellus_ Sars (59), p. 171, pl. LXXV.

_Oniscus asellus_ is one of the largest of our woodlice and it is also

probably the commonest, though _Porcellio scaber_ is in many places

quite as abundant. The body of _Oniscus_ is broad and expanded and the

colour is usually a slate grey with yellowish markings more or less

regularly arranged.

From the genus _Porcellio_ the species with which we are concerned

is at once distinguished by the three jointed flagellum. _Porcellio_

has but two joints and has, besides, a prominent lobe projecting from

the middle of the head, which is not seen in _Oniscus_. _Philoscia_,

although it has three joints to the flagellum, has a narrow abdomen

and lacks entirely the lateral lobes which are a feature of the other

genera of Oniscidæ.

_Oniscus fossor_ of Koch (34) was recognized by Kinahan and by Bate and

Westwood as a species. Dr. Scharff submitted specimens to Professor

Budde-Lund who found no differences between them and _Oniscus asellus_.

The former (63) mentions, however, that the characteristics of the

supposed species are those of young examples of _Oniscus asellus_, and

Professor Sars (59, p. 173) seems to be of the same opinion. Many young

examples of _Oniscus asellus_ that we have examined have a curious

whitish transverse band owing to the light colour of the dorsal plates

of the first abdominal segments. The flagellum also does not seem to

shew in young animals a distinct division into three joints.

[Illustration: FIG. 43.--FLAGELLUM AND LAST PEDUNCULAR JOINT OF THE

ANTENNA OF _Oniscus asellus_.]

_BRITISH LOCALITIES:--_

_England_: High Beach, Epping, including an albino; Maldon;

Brightlingsea; Iver; Hanwell; Eton; Kew; Pamber Forest;

Kingston-on-Soar; Bluebell Hill, Maidstone; (W.M.W.):

Lynmouth; (W.M.W. from J.T.C.).

_Scotland_: (Scharff, 63). Dinnet, Aberdeenshire; (W.M.W. from

Madame Christen).

_Ireland_: (Scharff, 63). Yellow form with black spots, Donegal (R.W.)

_FOREIGN DISTRIBUTION:--_

_Europe_: Almost throughout; (12): France; (25): Spain; (12):

Sweden Norway; Denmark; Germany; Holland; Italy; Iceland; (59):

Faroe Islands; Thorsharn; (R.F.S.)

_Africa_: Azores; (24).

_America_: Greenland; (59): North America; (Budde-Lund).

_Genus_--=PHILOSCIA= Latreille, 1804 (37), p. 43.

_Flagellum with three joints; abdomen narrow; head without lateral

lobes._

If any further differences of an obvious kind be required to

distinguish _Philoscia_ from _Oniscus_, one at least will be found in

the much greater development of the hinder legs in the former genus.

=Philoscia muscorum= Scopoli. PLATE X.

[Not of Lereboullet, which is an _Oniscus_, see Bate and Westwood (1).]

1763 _Oniscus muscorum_ Scopoli (67), p. 415.

1793 _Oniscus sylvestris_ Fabricius (26), p. 397.

1793 _Oniscus agilis_ Koch in Panzer (51), part 9, pl. XXIV.

1833 _Philoscia marmorata_ Brandt (3), p. 183.

1838 _Ligia melanocephala_ Koch (34), part 22, pl. XVIII.

1847 _Zia melanocephala_ Koch (38), part 40, pl. I. p. 212.

1868 _Philoscia muscorum_ Bate and Westwood (1), p. 450.

1898 _Philoscia muscorum_ Sars (59), p. 174, pl. LXXVI., fig. 1.

This species lives chiefly at the roots of grass and under the stones

or sticks that lie among it. _Philoscia muscorum_ has a very smooth and

shining body, and its long legs enable it to move very rapidly. The

ground colour of its dorsal surface varies from light yellow to deep

brown. There are characteristic dark markings down the middle of the

thorax and on the sides, between which are lighter patches. In dark

coloured specimens the markings are by no means so evident.

[Illustration: FIG. 44.--FLAGELLUM AND LAST PEDUNCULAR JOINT OF THE

ANTENNA OF _Philoscia muscorum_.]

_BRITISH LOCALITIES:--_

_England_: High Beach, Epping; Warley; (W.M.W.): Maldon; (W.M.W.

from R.M.): Kew; Langley; Hanwell, yellow variation; Bluebell

Hill, Maidstone; (W.M.W.): Liphook; (C.S.): Pamber Forest;

Kingston-on-Soar; (W.M.W.)

_Scotland_: (Scott, 68).

_Ireland_: Almost throughout; (Scharff, 63).

_FOREIGN DISTRIBUTION:--_

_Europe_: France; (25): Spain; (12): Sicily; (19): Hertsogovinia;

(22): Sweden; (21): Norway; Denmark; Prussia; Germany; Holland;

Poland; Austria; Italy; (59): Sardinia; (21).

_Africa_: Algeria; Tunis; (24).

=Philoscia couchii= Kinahan. PLATE XI.

1858 _Philoscia couchii_ Kinahan (33), p. 195, pl. XXIII., fig. 4.

1868 _Philoscia couchii_ Bate and Westwood (1), p.

1885 _Ligidium couchii_ Budde-Lund (8), p. 257.

1885 _Philoscia longicornis_ Budde-Lund (8), p. 221.

1897 _Philoscia couchii_ Dollfus (21), p. 72, pl. I., fig. 1.

_Philoscia couchii_ is an inhabitant of the sea-side; it is smaller

than the last species, its colour to the naked eye is a uniform

lead-grey, and its antennæ are very large (compared with its size) and

hairy.

This species was discovered by Professor Kinahan when in the company of

Messrs. Bate and Westwood near Polperro in Cornwall in the year 1858,

and dried specimens presented by him are in the British Museum (Natural

History).

_BRITISH LOCALITIES:--_

_England_: Talland Cove; Polperro; (Bate and Westwood, 1): Salcombe,

Devon; (Norman, 49): Meadefoot, Torquay; (Stebbing in 49).

_FOREIGN DISTRIBUTION:--_

_Europe_: France; (25): Spain; (12): Sicily; (19): Sebastopol;

(Norman, 49).

_Africa_: Azores; Canaries; Morocco; Algiers; Tunis: Egypt

Senegal; (24).

_Atlantic Isles_: Canaries; Azores; (21).

_Asia_: Syracuse; Bazone (18).

[Illustration: FIG. 45.--FLAGELLUM AND LAST PEDUNCULAR JOINT OF THE

ANTENNA OF _Philoscia couchii_.]

_Genus_--=PLATYARTHRUS= Brandt, 1833 (3), p. 174.

[_Typhloniscus_ Schöbl (66), p. 279.]

_Flagellum with one joint; eyes wanting; abdomen broad; habitat, ants'

nests._

The broad body, which is much flattened, and the very thick

antennæ distinguish _Platyarthrus_ from the other small woodlice

(Trichoniscidæ).

=Platyarthrus hoffmannseggii= Brandt. PLATE XII.

1833 _Platyarthrus hoffmannseggii_ Brandt (3), p. 174, pl. IV.,

fig. 10.

1844 _Itea crassicornis_ Koch (34), part 36, pl. V.

1860 _Typhloniscus steinii_ Schöbl (66), p. 282.

1868 _Platyarthrus hoffmannseggii_ Bate and Westwood (1), p. 464.

1898 _Platyarthrus hoffmannseggii_ Sars (59), p. 175, pl. LXXVI.,

fig. 2.

Up to the present this is the only woodlouse which has been found in

the nests of British ants. It is small and oval, its colour is white,

and its body is covered with tubercles. The edges of its side plates

are toothed, its flagellum has but a single joint and it has no eyes.

Miss Kate Hall tells us that, if very hungry, ants in captivity will

kill and eat _Platyarthrus_. With regard to its own food, Lord Avebury

has favoured us with the opinion that it lives on the spores of the

lower plants, such as would be found in the ants' nest.

[Illustration: FIG. 46.--FLAGELLUM AND LAST PEDUNCULAR JOINT OF THE

ANTENNA OF _Platyarthrus hoffmannseggii_.]

_BRITISH LOCALITIES:--_

_England_: Warley; Hanwell; West Drayton; Langley;

Kingston-on-Soar; Bluebell Hill, Maidstone; (W.M.W.): Berkhamsted;

Salcombe; Devon; Cheddar Cliffs, Somerset; (Norman, 49): Ide, near

Exeter; (Parfitt, 53): Torquay; (Stebbing in 49); Lulworth Cove;

(Rev. A. R. Hogan _teste_ Bate and Westwood, 1): Hammersmith;

Oxford; Berry Head, Torquay; Plymouth; (Bate and Westwood, 1): In

the nest of _Myrmica rubra_, Newton Ferrers (E. E. Lowe).

_Scotland_: Banff; (Thomas Edward in 49).

_Ireland_: Leixlip, Co. Dublin; Lismore, Co. Waterford; Glengariff,

Co. Cork; (Scharff, 63): Bagenalstown, Co. Carlow; (64).

_FOREIGN DISTRIBUTION:--_

_Europe_: France; (28): Spain; (12): Denmark; Germany; Holland;

Bohemia; Austria; Tyrol; Helvetia; (59).

* * * * *

NOTE.--In the genera which follow, air-tubes or air-cavities

(tracheæ) are present in the outer plates of the abdominal

appendages, 1 and 2, or 1 to 5. The appendages in question have

in consequence a milk-white appearance in the living animal

owing to the fact that the enclosed air reflects white light.

Considerable interest attaches to the study of these tracheæ,

which have the same function as those of insects, but which have

been independently developed. To emphasise the latter fact the

structures are often termed "pseudotracheæ."

_Genus_--=PORCELLIO= Latreille, 1804 (37), p. 45.

_Flagellum, with two joints; abdomen, broad; frontal lobe projecting._

_Porcellio_ is easily separated from the previous genera--_Oniscus_,

_Philoscia_, and _Platyarthrus_--by its two-jointed flagellum. The

fact that the abdomen is not abruptly narrowed separates it from

_Metoponorthus_, which also lacks the prominent frontal lobe so

characteristic of _Porcellio_. The species of this genera might be

confused with _Cyclisticus_ which has two joints to the flagellum and

a broad abdomen, but the latter genus has the power of rolling itself

into a ball, while its frontal lobe is very small, and the first

segment of its thorax is comparatively larger than in any species of

_Porcellio_.

=Porcellio scaber= Latreille. PLATE XIII.

1804 _Porcellio scaber_ Latreille (37), p. 45.

1818 _Oniscus granulatus_ Lamark (36), p. 261.

1818 _Porcellio nigra_ Say (62), p. 432.

1840 _Porcellio brandtii_ Milne-Edwards (46), p. 168.

1840 _Porcellio dubius_ Koch (34), part 34, pl. VIII.

1847 _Porcellio asper_ Koch (35), p. 207, pl. VIII., fig. 98.

1857 _Porcellio montezumæ_ Saussure (60), p. 207.

1865 _Porcellio paulensis_ Heller (31), p. 136, p. XII., fig. 5.

1868 _Porcellio scaber_ Bate and Westwood (1), p. 475.

1876 _Porcellio graniger_ Miers (44), p. 223.

1885 _Porcellio graniger_ Budde-Lund (8), p. 149.

1898 _Porcellio scaber_ Sars (59), p. 176, pl. LXXVII.

The body of _Porcellio scaber_ is densely covered with tubercles. Its

colour is usually of a very dark grey, but at times it is quite red or

variegated with yellow. Albino specimens have been recorded. The two

joints of the flagellum are of the same length and together equal that

of the last joint of the peduncle. Air-tubes are present in the outer

plates of the first two abdominal appendages.

[Illustration: FIG. 47.--FLAGELLUM AND LAST PEDUNCULAR JOINT OF THE

ANTENNA OF _Porcellio scaber_.]

_BRITISH LOCALITIES:--_

_England_: High Beach, Epping; Warley; Brightlingsea; (W.M.W.):

Maldon; (W.M.W. from R.M.): Langley; Kew; Skirmett; Pamber Forest;

(W.M.W.): Liphook; (C.S.): Stoke-on-Trent; Kingston-on-Soar;

(W.M.W.)

_Scotland_: Dinnet (W.M.W. from Madame Christen).

_Ireland_: Common everywhere; (Scharff, 63.)

_FOREIGN DISTRIBUTION:--_

_Europe_: Throughout; (59): France; (28): Spain; (15): Iceland;

(59): Faroe Isles--Thorsharn and Naalsoe--(R.F.S. and B.M., N.

Annadale).

_America_: Greenland; North America; Sandwich Isles; (B.M.);

Mexico; (59): St. Paul; St. Croix; (59); Ascension; Tristan

d'Acunha; (23)

_Asia_: Ceylon; Kamtschatka: (23).

_Australia_: Melbourne; Sydney; Tasmania; New Zealand; (B.M.,

Chilton).

_Africa_: Azores; Canaries; Cape of Good Hope; (24).

=Porcellio pictus= Brandt and Ratzeburg. PLATE XIV.

1833 _Porcellio pictus_ Brandt and Razteburg (4), p. 78, pl. 12,

fig. 5.

1839 _Porcellio melanocephalus_ Koch (34), part 28, pl. XVIII.

1853 _Porcellio melanocephalus_ Schnitzler (65), p. 24.

1856 _Porcellio mixtus_ Fitch (29), p. 120.

1868 _Porcellio pictus_ Bate and Westwood (1), p.

1898 _Porcellio pictus_ Sars (59), p. 177. pl. LXXVII., fig. 1.

There are tubercles on the body of _Porcellio pictus_, which is a

striking looking animal. Its head is black with the lateral lobes

curved outwards; there is a dark band down the middle of the back and

commonly two others on each side, with more or less conspicuous yellow

markings between.

The distal (terminal) joint of the flagellum is but half the length of

the proximal one and the last peduncular joint is longer than the two

combined.

The abdominal appendages--1 and 2--are provided with air-tubes.

[Illustration: FIG. 48.--FLAGELLUM AND LAST PEDUNCULAR JOINT OF THE

ANTENNA OF _Porcellio pictus_.]

_BRITISH LOCALITIES:--_

_England_: Maldon; (W.M.W. from R.M.): Chislehurst; (Bate and

Westwood, 1): Cooper's Hill, near Cheltenham; (Norman, 49):

Exeter; (Parfitt, 53): Kent; (Bate and Westwood, 1.)

_Scotland_: Between Leith and Portobello; (Scott, 68): Cumbrae

(Scott, 68a): Ayrshire; (Boyd in Norman, 49): Banff; (T. Edwards

in Norman, 49).

_Ireland_: Dublin; Belfast; (Bate and Westwood, 1): Galway;

Maryborough; Queen's Co., Castel; and Caher Co. Tipperary; (R.F.S.)

_FOREIGN DISTRIBUTION:--_

_Europe_: France; (25): North, West-Central, and East Europe; (8):

Sweden; Norway; Denmark; Germany; Hungary; Russia; (59).

_North America_: (8).

=Porcellio dilatatus= Brandt. PLATE XV.

1833 _Porcellio dilatatus_ Brandt and Ratzeburg (4), p. 78, pl. 12.,

fig. 6.

1840 _Porcellio scaber_ Milne-Edwards (not Latreille) (46), p. 167.

1868 _Porcellio dilatatus_ Bate and Westwood (1), p.

1898 _Porcellio dilatatus_ Sars (59), p. 179, pl. LXXVII., fig. 2.

The fact that _Porcellio dilatatus_ is more than half as broad as it is

long, at once distinguishes it from the other species of _Porcellio_.

It is tuberculated and of somewhat a lighter grey than _Porcellio

scaber_ usually is. The two species agree in having the two joints of

the flagellum equal, but the last peduncular joint, as in _Porcellio

pictus_, is longer than the flagellum.

As in the two preceding species, air-tubes are found in the outer

plates of the appendages on the first two abdominal segments.

_Porcellio dilatatus_ is to be looked for near houses.

[Illustration: FIG. 49.--FLAGELLUM AND LAST PEDUNCULAR JOINT OF THE

ANTENNA OF _Porcellio dilatatus_.]

_BRITISH LOCALITIES:--_

_England_: Maldon; (W.M.W. from R.M.): Eton; (Stebbing from

W.M.W., 71a): Berkhamsted; (Norman, 50): Headley, Surrey; Ventnor;

(Stebbing in Norman, 49).

_Ireland_: Dublin; (Scharff, 63): Dundrum; (Scharff in Norman,

50): Galway; Roundstone; (R.F.S.): Belfast; (C. W. Buckle, Irish

Nat., Vol. XI. (1902), p. 43).

_FOREIGN DISTRIBUTION:--_

_Europe_: France; (25): Spain; (12 ): Denmark; Norway; Germany;

Poland; Holland; (59).

_Africa_: Madeira; Azores; (24).

_Australia_: New Guinea; (59).

=Porcellio rathkei= Brandt. PLATE XVI.

1833 _Porcellio rathkei_ Brandt (3), p. 177, fig. 10.

1833 _Porcellio ferrugineus_ Brandt (3), p. 178.

1840 _Porcellio trilineatus_ Koch (34), part 34, pl. IX.

1853 _Porcellio trivittatus_ Lereboullet (39), p. 54, pl. I.,

figs. 13 and 14.

1853 _Porcellio tetramoerus_ Schnitzler (65), p. 24.

1853 _Porcellio striatus_ Schnitzler (65), p. 24.