—— 
230 HELIX POMATIA. 
the country, its line of advance marking the area intervening between the 
southern limits of the Boreal region ‘of Milachevich and the northern 
boundary of the southern fauna “of Drouet, and the route is, therefore, 
strongly confirmatory of the suggested chief line of migration! from the 
European region advocated in the present work. 
Beyond the true range of the species, and overlapping its confines, at 
many points, or isolated in more or less restricted regions, there are, how- 
ever, several closely-allied species, as Helix cincta, H. ligata, H. lucor um, 
ed melunostuma, Hl. radiosa, H. obtusata, ete., which are probably the 
modified earlier offshoots from a common ancestral form, and, therefore, 
occupying outlying or detached districts more or less remote from the 
assumed chief evolutionary area now inhabited by Helix pomatia. 
In the British Isles, its distribution is distinctly southern, and almost 
confined to calcareous soils, its metropolis being the Thames valley ; it 
extends westward as far as the Cotswolds, and, according to Mr. Royal, 
Dawson, lives as far north as Norfolk. | 
It has hitherto been a very general belief that Helix pomatiu was’ 
introduced into this country, as food, by the Romans, this belief being 
mainly based upon the discovery of its shell among the buried relics of the 
Roman occupation, and its comparative abundance in a living state in the 
immediate vicinity of several Roman stations or encampments. 
The probability of its importation into this country by them is rendered 
less probable by the fact that this species is not found near Rome, not 
having, even yet, spread so far to the south, its place being filled by 
H. lucor um, H. cincta, and other allied species, but the discovery of its 
fossilized remains in several undoubtedly pre-Roman deposits would seem, 
however, to finally dispose of any doubts of its beimg really native, and we 
may, therefore, now regard the species as a true denizen of this country. 
Though it is beyond question that very numerous attempts have been 
made in the past, and even at the present day, to establish this mollusk 
in districts where it was not known to occur, yet these efforts are almost 
invariably unsuccessful and there is little doubt that 7. pomutia originally 
reached this country by natural means, and that its diffusion over the 
country has been due to legitimate methods of dispersal with little or no 
voluntary assistance by man. 
INGLAND AND WALES 
Channel Isles—Messrs. Cooke and Gwatkin record that the late Dr. Lukis 
endeavoured to colonize //. pomatia in Guernsey, though apparently unsuccessfully 
(Q. J. of Conch., 1878, p. 333). 
CHANNEL. 
Devon S.—E. Parfitt records finding a single living example by the side of the 
Exeter Canal in 1862 (now in Exeter Museum '), but thought it must have been an 
escape (Trans. Devonsh. Ass., 1875-4, vi., p. 634). 
Wilts. N.—A single cane was recorded in 1805 by Colonel Montagu from 
Devizes, where it has also been found in recent years by Mr. C. D. Heginbotham 
and Mr. G. Trevor Lyle. Mr. H. Cunnington has also collected it in June 1883 
on Roundway Hill, near the same town; Mr. C. N. Bromehead found specimens at 
the south-east corner of East Croft on the edge of the forest, near Puthall Gate, 
Marlborough; and Rey. J. E. Vize records it from woods near Chilton and Ramsbury. 
Wilts. S.— Rare at Salisbury (J. E. Vize, Wilts. Mag., 1866, p. 279). 
Dorset—Not uncommon in Dorsetshire (Da Costa, Brit. Coneh., 1778, p. 71). 
Hants. S.—Rey. W. H. Hawker attempted to colonize or establish the species 
at Horndean during 1855 (Linnean Trans., 1855). 
1 Monog. i., 392, and maps. 
