HELIX PISANA (the Banded Snail) (Pl. VIII., fig. 66). The specific name, "Pisana," was given to this species from its having been first found at Pisa.

This species is the most beautiful of our snails. The shell is solid, moderately glossy, about a fourth of an inch in diameter, and half an inch high, with five whorls of yellowish-white ornamented with numerous brown spiral bands, interrupted by short oblique streaks of the same colour, giving the upper surface a speckled appearance.

The aperture is rounded, rose-coloured in the interior, with an internal rib: the umbilicus is narrow, nearly closed by the reflected margin of the lip. The dental formula is 35.1.35

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In Great Britain it is only found on the coastline. On the sand-banks between Tenby and Kilter Point it is very numerous. Another locality is St. Ives, where in the hot weather the snails have been observed buried in the sand at the roots of Carex arenaria to the depth of some inches. It also occurs abundantly near Dublin, and in Jersey. On the Continent it is confined to the southern countries, but it is found at Constantinople, with such western species as H. Cartusiana, H. virgata, and H. ericetorum.

HELIX VIRGATA-(the Zoned Snail) (Pl. VIII., fig. 80).—This snail, with H. caperata, H. ericetorum, and Bulimus acutus, affects the dry stunted

vegetation on downs and heaths. It is generally found in greater abundance on the sea-coast, but occurs in many inland districts. It is a very abundant and gregarious species, adhering in clusters to the stems of various plants. During the hot weather they bury themselves about the roots of plants; but after a shower of rain they appear in such abundante that they are supposed by country folks to come down from the clouds with the rain.

Helix virgata has the propensity of feeding upon Coccinella and other small insects, and is itself, with its congeners, accidentally eaten by sheep pasturing on the downs and commons, where it occurs in such profusion. "For it is indeed impossible that the sheep can browse on the short grass without devouring a prodigious quantity of them, especially in the night, or after rain, when they ascend the stunted blades;" and in the South of England it is a prevalent, and probably a correct opinion, that these snails contribute much. to the fattening of sheep. The superiority of the Dartmoor and Southdown mutton is presumed to be attributable to the flavour imparted to it by these mollusks. The distoma, or fluke of sheep, possibly may be derived from the embryonic form which lives parasitically in the snail.

Some authors have remarked, from their own observations, in particular localities, that it is

never found in company with H. ericetorum. This observation is not of general application.

The shell of the "zoned snail" is conical; white, or cream-colour; with a single dark-brown band in the middle of the last whorl, and with many smaller ones beneath. It varies much in colour and external markings. A pretty variety has two narrow brown bands on the under surface, between which is a row of brown spots, each connected by a narrow brown band. Within the aperture of the shell, and at a distance of two lines from its reflected margin, is a narrow but well-marked ridge, usually corresponding to that of the mouth, which is a purplish-brown.

The whorls are six in number, and the shell has an average diameter of a fourth of an inch. A few specimens collected by me in corn-fields on the chalk downs, near Eastbourne, have a breadth of seven-tenths of an inch. Mr. J. G. Jeffreys has seen specimens from Weymouth a tenth of an inch broader.

HELIX CAPERATA— (the -(the Wrinkled Snail) (Pl. VIII., fig. 78).—So called from the numerous concentric rib-like striæ upon the whorls; it is further to be distinguished from H. virgata by its depressed spire and larger umbilicus, and is usually of a much smaller size. The colour of the shell is usually of a dull yellowish-white, with narrow brown bands. The spire is tipped

with black or brown, from which latter character it is known by another name, that of H. fasciolata. The dental formula is 25.1.25. It is extremely

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variable in colour, from white to reddish-brown, and in the number and colour of the bands.

It is generally associated with the last species, but is not so abundant; it is, however, more widely distributed.

HELIX CANTIANA-(the Kentish Snail) (Pl. VIII., fig. 64).—The shell of this snail is subglobose, thin, semi-transparent, and yellowishwhite, with a tinge of pale rose-colour, especially towards the aperture. The margin of the aperture is thin and but slightly reflected, and at a little distance from its edge is an internal thick and white rib; there is a small narrow and deep umbilicus; the whorls are six or seven in number; the diameter of the shell is threefourths of an inch. Young shells want the internal rib, and are clothed with short hairs, which disappear in the adult. The dental formula is 40.1.40

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H. Cantiana is a southern species in Europe, and attains its northern limit in England; it is indigenous in the south-eastern counties. It is abundant on nettles, and plants in wet places, and by ditches in Kent and Sussex, and in the counties bordering the river Thames.

It is plentiful on the downs at Bedminster, &c.,

in the vicinity of Bristol; Swansea; and on the banks of the river Tyne, about Newcastle: in these localities it is said to have been introduced with ballast.

In the Bristol district it was first observed between Brislington and Keynsham, in 1825. Gardner, in his "Natural History of Staffordshire," says, "it is not rare in the Dovesdale and Wetton valleys." And as it occurs also in North Gloucestershire, at Evesham, there is no reason to doubt that the Kentish snail is truly indigenous to the western counties of England.

HELIX CARTUSIANA-(Pl. VIII., fig. 70).-So called from its having been first discovered near a Carthusian Monastery; it is closely related to the Kentish snail, and possesses a white internal rib and an umbilicus, as in that species, but differs from it in its much smaller size, being about half an inch in diameter, more solid and not so glossy, nearly opaque; it is more depressed, and the umbilicus is minute.

It is found on the short herbage clothing the chalk downs of the Kentish and Sussex coasts. It appears to be confined to the neighbourhood of the sea, and to the chalk soil; though there are many favourable localities for it along the coast intervening between Folkestone and Eastbourne, yet I have failed to find, though often sought for it. The same is true of H. ericetorum