ZONITOIDES EXCAVATUS. 137 
Variation.—'he only modification hitherto noted of this species is 
the crystalline variety, which is linked with the type by the very pale 
yellow form. 
: 4 VARIATION IN SHELL. 
Var. vitrina Jeffreys, Brit. Conch., 1862, p. 168. 
Zonites excavatus var. hyalina Jeffreys, Ann. Nat. Hist., 1858, p. 47 (nomen nudum). 
SHELL greenish-white and semi-transparent. 
The distribution of this variety is somewhat erratic, and would appear to 
indicate the environment as a potent predisposing factor in its production. Mr. 
F. Taylor remarks that in Holden Clough, near Oldham, the type abounds, and 
none of the variety have been found, whereas a short distance away the variety 
is equally common with the type. 
ENGLAND AND WALES. 
Devon S.—Plentiful in one spot, Erme Woods (E. D. Marquand, J. of Conch., 
Oct. 1899, p. 138). Ivy Bridge, W. Webster. 
Devon N.—New Bridge, near Barnstaple! F. J. Partridge. 
Somerset S.—Dulverton, 1903 ! Hugh Watson. 
Dorset— Morden ! E. Ruthven Sykes. 
Hants. S.—An intermediate transparent pale yellow form numerous in a small 
copse on Roeshot Hill, Christchurch, type apparently absent, Oct. 1885 ! C. Ashford. 
Bucks.—Burnham Beeches, G. D. H. Carpenter. 
Warwick—At foot of a poplar in a damp meadow between Knowle and Pack- 
wood, Sept. 1874! W. G. Blatch. Sutton Coldfield, with type, 1899, Guy Breeden. 
Pembroke—Narberth, May 1885 ! Charles G. Barrett. 
Cardigan—Borth, Aug. 1907, A. H. Jowett-Murray. 
Merioneth—Dolgelly, July 1886! F. G. Fenn. Fairbourne, where the variety 
far outnumbered the type, Aug. 1907, A. H. Jowett-Murray. 
Carmarthen—Var. hyalina, Trosserch Wood (J. G. Jeffreys, ].c.). 
Cheshire— Marple, Sept. 1885! T. Rogers. Marston Forge, Northwich, Oct. 1885 ! 
C. Oldham. Owley Wood and Marbury, B. R. Lucas. Disley, K. H. Jones. East- 
ham, 1885! E. Collier.  Butt’s Clough and Rostherne (Milne and Oldham, J. of C., 
Jan. 1894, p. 318). A bleak hillside, opposite Parkgate railway station, F. Taylor. 
Lancashire S.—Drinkwater Park, near Prestwich, 1884, E. Collier. Hough 
End ! Thomas Rogers. Warrington and Agecroft near Manchester ! G. Jackson. 
Bardsley near Oldham, with type, F. Taylor. 
Lancashire Mid—Crystalline specimens in British Museum, labelled ‘ Preston.” 
York S.W.—Golcar Wood ! J. Whitwham. Hey Wood near Honley, more 
plentiful than the type, March 1875, J. Conacher. Bulleliffe Wood ! G. Taylor. 
Durham—Gibside Woods ! J. Alder. 
Cumberland—Common in the Lake district, Bassenthwaite, ete., W. J. Farrer. 
IRELAND. 
Donegal— Wood at Ardara, 1900 ! R. Welch. 
Dublin—Dublin, W. White Walpole. 
Mayo W.—Delphi, with type, April 1897, R. Welch. 
Galway W.—Connemara (Jeffreys’ Brit. Conch., 1862, p. 169). 
Waterford— Common in wood, Glendine, July 1907 ! W. Denison Roebuek. 
Cork N.—With type, Lough Allua, July 1907! R. A. Phillips. 
Cork S.—Schull (Phillips’ Cork List, 1894). Glengariff, 1891! R. I. Scharff. 
Kerry—Cloonee, with type (Dr. Chaster). Elsewhere the var. is the most 
prevalent form, and is especially abundant at Mucksna Wood in Kenmare demesne, 
and at Inchiquin (R. Standen, Irish Nat., Sept. 1898, p. 220). Derrynane, 1892 ! 
Kh. F. Seharff. Common with type in woods at Glengariff; and on Tore Mountain, 
July 1907 (Stelfox and Milne, Irish Nat., Sept. 1907, p. 288). 
Geographical Distribution.—Zonitoides excuvatus is a species that 
has probably been misunderstood and overlooked on the continent, as it 
is very unlikely to be so strictly confined to the limits of the British Isles, 
as its recorded distribution would indicate. 
The only extra-British localities known up to the present time are 
Esschen near Antwerp, Belgium, from whence it is recorded by M. Colbeau, 
and the vicinity of Flensburg in Schleswig. 
In the British Isles it is somewhat sporadically distributed over England, 
Ireland, and Scotland, but has not yet been authenticated for East Anglia. 
