CONCHOLOGY. 



79 



Univalves, strongly in a longitudinal direction ; mouth narrow, 

 *■* "Y"""' sub-oval, contracted at both ends ; outer lip somewhat 

 expanded, and a little thickened at the back ; length 

 three-tenths of an inch, breadth one-tenth. 

 Test. Brit. tab. 1 5. fig. 7. 

 Found by Mr Bryer on the shore between Wey- 

 mouth and Portland Island. 

 Labiosa 22. Labiosa. Shell sub-conic, sub-pellucid, with se- 



ven or eight flattish spires ending in a fine point, and 

 furnished with from fifteen to eighteen faint ribs on the 

 ' three largest whorls ; the superior volutions smooth ; 

 lips thickened, within white.; the back of the outer lip 

 a little gibbose ; length rather more than a quarter of 

 an inch, breadth nearly one half of its length. 

 Test. Brit. tab. 13. fig. 7- 

 A shell not uncommon in England. Has been found 

 in Scotland, on the coast at Dunbar, by Mr Laskey. 

 Subulau, 23. Subulata. Shell subulate, smooth, glossy, with 

 about ten scarcely defined whorls ; colour white, mark- 

 ed with two faint yellowish lines, which follow the spi- 

 ral turn of the shell, but become obsolete towards the 

 apex ; mouth narrow, contracted at the interior angle ; 

 length about three-quarters of an inch. 

 Brit. Shells, tab. 172. 

 First noticed by Da Costa, from Exmouth in Devon- 

 shire ; Mr Donovan received it from Weymouth ; and 

 Mr Laskey found it at Dunbar, 

 .jea, 24. Petrcea. Shell strong, conic, opake, with five 



spires, occupying nearly two-thirds of the length of the 

 shell, and irregularly wrinkled ; mouth lunated ; outer 

 lip considerably projecting, operculum corneus ; length 

 about a quarter of an inch, breadth two-tenths of an 

 inch. 



Test. Brit. p. 403. 

 Found on the coast of Devon and Dorset by Mr 

 Montagu. 



Family II. GLOBOSE. 



The shells which this family includes are, in form, 

 somewhat 'orbicular. The first, or body whorl, is large; 

 the remaining volutions decrease in size to the apex ra- 

 ther suddenly. The apex is seldom much produced. 

 In consequence of this shape of the whorls, the shell is 

 broader than it is long. The mouth is entire, and of a 

 roundish form. The common garden slug {Helix as- 

 persa) may be considered as the type of the family. At 

 present we shall consider the British species under the 

 three following genera : Helix, Nerita, and Trochus. 



Genus XVI. Helix. 



VI- iS7;e/Z subglobose, with a convex spire; the ope?iing en- 



L1X ' tire, wider than long, and diminished in its upper part 

 by the projection of the last turn but one of the spire. 



Obs. The shells of this genus, with a few excep- 

 tions, are inhabitants of the land. They are usually 

 translucent and brittle. The species of the genus ad- 

 mit of distribution into two subdivisions. The first 

 will contain those shells which are furnished with a pil- 

 lar cavity, or in which the base of the pillar is perfo- 

 rated. The second will include those in which the base 

 of the pillar is closed. The land shells of this subdivi- 

 sion have the base of the pillar perforated in the earlier 

 stages of their growth, and until the margin of the 

 mouth is formed. 



A. Base perforated. 



Pomatia, 1- Pomatia. Shell sub-globose, translucent, yellow- 



ish brown with five rounded whorls wrinkled longitu- Univalve- 

 dinally ; mouth semilunated ; margin a little thicken- """"V" 5 """ 

 ed ; inner lip much reflected over the pillar cavity ; di- 

 ameter about two inches. 



Brit. Zool. tab. 84. fig. 128, 

 The name of this species is derived, not from any 

 thing relating to an orchard, but from napx, an oper- 

 culum, it having a very strong one. It is not indige- 

 nous, or originally a native of Britain, but is a natural- 

 ized species. It Was first introduced into England by 

 a Mr Howard about the middle of the 16th century. 

 In the southern counties it is very common. We have 

 likewise observed them in the garden of Patrick Neill, 

 Esq. at Canonmills, near Edinburgh, into which they 

 were lately introduced. They were a favourite dish 

 among the Romans. 



2. Virgata. Shell with six rounded volutions con- Virgataj 

 siderably produced. Colour white tinged with black, 



with one dark purplish brown band on the middle of 

 the body ; mouth lunated, lip thin, pale purplish brown, 

 with a white thread-like elevation round the margin ; 

 pillar cavity deep ; length generally half an inch. 



Test. Brit. tab. 24. fig. 1. 



Brit Shells, tab. 65. H. Zonaria. 

 Inhabits dry banks and sandy soils in various parts 

 of England. 



3. Cingenda. Shell sub-pellucid, with five whorls ; Cingenda, 

 the larger ones are a little angulated at the top, apex 



dark, obtuse and depressed ; colour yellowish white, 

 with several small bands of chesnut running spirally up 

 the shell ; the base has generally one circular band; 

 minutely striated longitudinally and transversely ; pil- 

 lar cavity very small ; breadth at the base three quar- 

 ters of an inch ; height half an inch. 



Brit. Zool. tab. 85. fig. 133. H. Zonaria. 



Lin. Trans, vol. viii. tab. 5. fig. 6. 

 Found by Mr Montagu at Lenby in South Wales, 

 and Mr Racket has found it near St Ives in Cornwall. 

 It lives upon maritime plants. 



4. Rufescens. Shell rufous with six whorls, well se- Rufescens, 

 parated, a little rounded wrinkled across ; edge of the 



lower volution sub-carinated ; mouth lunated ; outer 

 lip thin, and a little reflected at the lower angle ; pillar 

 cavity large and deep; diameter at the base half aa 

 inch. 



Brit. Shells, tab. 57. fig. 1. 1. 

 Test. Brit. tab. 23. fig. 2. 

 This shell, when young, is thickly covered with 

 short hairs seated on the epidermis. It inhabits moist 

 woods and under stones. It is very common in Eng- 

 land and Scotland. 



5. Cantiana. Shell with six volutions, rounded, Cantiana, 

 well defined by the separating line; mouth lunated; 

 margin a little thickened, inner lip reflected ; pillar ca- 

 vity narrow but deep. Diameter at the base above 



three quarters of an inch ; height half an inch. 



Brit. Shells, tab. 157- fig. 2. 2. H. pallida. 

 This species somewhat resembles the preceding ; it 

 is however larger, of a lighter colour, and has a small- 

 er pillar cavity. It is found in meadows and hedges in 

 Kent, Surry, and Dorset. 



6. Hispida. Shell sub-globose, thin, fragile, with Hispida, 

 five rounded volutions of a light horn-colour, covered 



with fine thick-set short whitish hairs ; apex flattened ; 

 mouth lunated ; inner lip a little reflected ; pillar cavi- 

 ty small, round ; diameter about a quarter of an inch. 

 Test. Brit. tab. 23. fig. 3. 

 Found among moss in England, not uncommon. We 

 have found it frequently in Scotland The shape of 



