302 MOLLUSCA. PECTINIBRANCHIA. Turritella. 



SI 2. p. decussata. — Whorls eight or nine, strongly striated 

 transversely ; minutely striated spirally. 



Helix dec. Mont. Test. Brit. 399. t. xv. f. 1 — On the shore at Wey- 



mouth, Mr Bryer. 



Length /gths of an inch ; breadth ^^th ; white, slender ; whorls nearly 



flat, the separating line extremely fine ; aperture narrow, suboval, contract- 



ed at both ends ; outer-lip somewhat expanded, and a little thickened at the 



back ; inner lip slightly replicated. 



213. P. pallida. — Whorls six or seven, smooth ; outer-lip 

 arcuated. 



Turbo pal. Mont. Test. Brit. 325. t. xxi. f. 4 — In sand, Salcomb Bay. 

 Length ith of an inch ; breadth |ds less ; slender, tapering to a fine point ; 

 whorls separated by a well-defined line ; aperture suborbicular, a faint du- 

 plicature on the pillar-lip, forming behind a small cavity. 



In the Mineral Conchology, the following fossil shells are referred to the 

 genus, though it is more probable that they belong to Limnea or Paludina. 



1. P. orbicularis. — Conical, acute, smooth ; whorls about six, veutricose ; 

 aperture nearly round — Sower. Min. Conch, t. clxxv. f. \.— Fresh ivater Lime- 

 stone, Shalcomb, Isle of Wight. 



2. P. angulosa. — Conical, smooth ; whorls subcarinated ; aperture nearly 

 round. — Sower. Min. Conch, t. clxxv. f. 2. — Along with the last. 



3. P. minuta. — Elongated, smooth ; whorls five or six ; obscurely squared ; 

 aperture oblong. — Sower. Min. Conch, t. clxxv. f. 3. — Along with the last. 



Gen. XLIX. TURRITELLA.— SheU elongated ; the whorls 

 numerous, produced ; aperture wide ; the pillar-lip slightly 

 rounded. 



214. T. terehra. — Whorls about sixteen, with numerous spi- 

 ral ridges. 



Buccinum tenue, List. An. Ang. 161. Conch, t. nxci. f 57. Turbo Ter. 



Limu S. Syst. i. 1239. Penn. Brit. Zool. iv. 130. t. Lxxxi. f. 113. Mtmt. 



Test. Brit. 293 — Common. 

 Length sometimes exceeding two inches ; breadth of the body-whorl half 

 an inch, of a reddish or purplish brown ; whoi'ls sometimes eighteen in num- 

 ber, ending in a fine point ; the larger whorls rounded, with five or six pro- 

 minent ridges, besides smaller ones, crossed by the layers of growth. In the 

 young shells the ridges are less numerous, and the anteal edge of the body- 

 whorl is flattened. The aperture, in young shells, is subquadrangular ; in an 

 old specimen the outer lip is round and thin, and the pillar-lip nearly straight. 

 The animal is yellow, stiiped with dusky, with the tentacula short. — This 

 species resides in deep water, but is frequently thrown ashore after storms. 



215. T. exoleta. — Whorls about twelve, spirally striated, with 

 two broad rounded spiral ridges. 



Cochlea variegata. List. Conch, t. Dxci. f. 58. — Turbo exol. Limx. Syst. i. 

 1239 — Turbo cinctus, Don. Brit. Shells, t. xxii. f. 1. Mont. Test. 

 Brit. 295 On the English coast, rare. 



