ARION CIRCUMSCRIPTUS. 23 
at times persist to adult life, and this juvenile peculiarity in adults is not 
restricted to any particular form, but is probably more common amongst 
the individuals living near the outskirts of the geographical range of the 
species. 
The Arion celticus and A. nilssoni of Pollonera would appear to be 
passage forms, linking the present species with Arion hortensis, possessing 
the yellowish foot and coioured slime of the latter, but with the internal 
organization in practical accord with that of A. circumscriptus, and should, 
therefore, be viewed as extreme forms of the latter species. It should, how- 
ever, be noted that the external characters of A. ce/ticus cannot be very 
well-marked, as specimens sent by Pollonera to Dr. Simroth as that species 
were found to be anatomically quite identical with A. hortensis. 
VARIATIONS IN COLOUR AND MARKINGS OF ANIMAL. 
Var. leucophea Normand, Descr. Lim., 1852, p. 5. 
Arion leucopheus Normand, op. cit. 
Arion hortensis var. grisea Bourguignat, Mal. Grande Chartr., 1864, p. 30, pl. 1, f. 10. 
Arion anibiguus and var. armoricana Poll., Atti. Acc. Sc. Torino, 1889, p. 15, ff. 16-19. 
Arion subcarinatus Pollonera, Elenco Moll. Terr. Piem., 1885, p. 19. 
Arion celticus Pollonera, Sp. nuov. Arion Europ., 1887, p. 19, ff. 11, 22, 33, 37. 
Arion circumscriptus var. atripunctatus Cockerell, Conch., Sept. 1891, p. 34. 
Arion circumscriptus var. subalbida Cockerell, Brit. Nat., 1891, p. 101. 
Arion fasciatus var. griseus Collinge, Conch., 1892, p. 79. 
ANIMAL of a grey colour, with darker lateral banding ; foot-fringe with indis- 
tinct lineolations. 
This variety which, with its more closely related forms, really represents the 
typical form, is sometimes found in an apparently dwarfed condition, possibly not 
fully grown, and in this state has been distinguished by Dr. Bandon as var. minor. 
The var. leueophea s.str., as defined by Van den Broeck, is ashy-grey, tinged 
with lilac, lateral bands dark. : 
The sub-var. ambigua is ashy-grey, fuscons dorsally, foot and foot-fringe 
whitish, with a tinge of yellowish, and faint lineoles. 
The sub-var. armorieana has the sides pale ash colour, with back and shield 
maculated deep grey. 
The sub-var. atripunetata has the shield punctate with black. 
The sub-var. grisea is light silver-grey, with darker lateral banding. 
The sub-var. subalbida is grey laterally, opaque-white below and darker dors- 
ally, with dark lateral banding ; sole and foot-fringe creamy-white. 
The sub-var. eceltica is darkly olivaceous above, sides pale grey with dark 
variegations and lateral banding, foot and foot-fringe yellowish, faintly lineolate. 
ENGLAND. 
Dorset—Sub-var. ambigua (T. D. A. Cockerell, Conch., Sept. 1891, p. 33). Sub- 
var. subalbida, Bailey Gate (id., op. cit., p. 35). Sub-var. armoricana, Sturminster 
Marshall (id., l.c.). Sub-var. grisea, Chideock, Bridport, Aug. 1885 ! A. Belt. 
Hants. S.—Sub-var. celtica, Southampton, E. W. Swanton (Collinge, Conch., 
1892, ii., p. 77). 
Kent W.—Sub-var. ce/tica, Doddington, E. W. Swanton (Collinge, 1.c.). 
Hereford—Sub-var. grisea, Bishopswood Vicarage garden, June 1885! Rey. 
R. W. J. Smart. 
Notts.—Sub-var. ce/tica, near Newark, W. A. Gain. 
Lancashire S.—Sub-var. grisea, Knowsley near Liverpool, 1893 (W. E. Collinge, 
J. of Mal., 1893, p. 148). 
York S.W.—Sub-var. atripunctata, Lofthouse, May 1887, G. Roberts (T. D. A. 
Cockerell, op. cit.). 
IRELAND. 
Meath—An uniformly grey variety, New Grange, June 1892, R. F. Scharff. 
Dublin—Killakee, Oct. 1890; and garden, Leeson Park, Dublin, R. F. Scharff. 
Galway W.—Roundstone, March 1891, R. F. Scharf. 
CONTINENTAL DISTRIBUTION. 
France—Var. lewcophea is found around Valenciennes in the department of the 
Nord, and at Troyes in the Aube (Moquin-Tandon, Hist. Moll., 1855, p. 15). Sub- 
vars. celtica and armoricana, about Brest, the former being erroneously said to 
replace Arion hortensis in that district. Sub-var. grisea, Grande Chartreuse, [sére. 
Italy—Sub-var. ambigua, Bardonecehia and Boves, Piedmont. Sub-var. sib- 
carinata, Rosazza, Piedmont. 
