Balea. MOLLUSCA. PULMONIFERA. 271 



Gen. XXVI. BALEA. — Tentacula four ; pillar simple, 



98. B. perversa.- — Whorls eight or nine, tapering, rounded. 

 Buccinum alterum pellucidum subflavum, List. An. Ang. 124. — Turbo 



perversus, Mrnit. Test. Brit. 355. t. xi. f. 12. — Pupa fragilis, Drap^ 

 Moll. 68. — In moss at the roots of trees. 

 Length nearly half an inch, translucent, with minute sharp lines of growth ; 

 apex blunt ; whorls tapering regularly ; mouth rounded anteaUy, becoming 

 narrow at the retral external angle ; peristome thin on the body, with one 

 tooth, slightly reflected at the pillar, forming behind a small cavity. Ac- 

 cording to Lister, the individuals pair in March, a smaller with a larger.— 

 This genus, instituted by Mr Prideaux, has been described by Mr Gray, 

 Zool. Joum. No. i. 61. 



Gen. XXVII. CLAUSILIA.— Tentacula four ; piUar with 

 an attached pedunculated testaceous scale, for closing the 

 aperture. 



99. C. bidens. — W^horls eleven, smooth, glossy ; the pillai'- 

 scale emarginate. 



Buccinum exiguum. List. Conch, t. xli. large fig. — Helix bidens, Mull. 

 "Verm. 116. — Turbo bidens, Penn. Brit. Zool. iv. 131. — T. laminatus, 

 Mont. Test. Brit. 359. t. xi. f. 4 — CI. bidens, Drap. Moll. 68 Eng- 

 land. 

 Length about f ths of an inch ; whorls slightly rounded, and well defined 

 Ijy the separating fine; aperture rounded, subquadrangular; peristome ad- 

 hering to the body, slightly reflected at the pillar ; two conspicuous teeth or 

 folds on the body, lip, and three others, concealed within the aperture. 



100. C. perversa. — Whorls twelve, striated, aperture entire, 

 rounded ; pillar- scale entire. 



Buccinum pullum 'opacum ore compresso circiter denis spiris fastigia- 



tum, List. An. Ang. 123. Conch, t. xli. f. 39 — Helix perversa. Mull. 



Verm. 118.— Turbo bidens, Mont. Test. Brit. 357 — Clausilla rugosa, 



Drap. Moll. 73 — Turbo nigricans, Maton and Rackett, Linn. Trans. 



viii. 180 — In walls and trees, common. 



Length about half an inch, somewhat swollen in the middle, of a brown colour. 



Whorls rounded at first, becoming more flat towards the mouth ; lines of 



growth distinct ; aperture detached from the body-whorl, rounded anteally, 



narrow retrally, with a ridge on the body-whorl behind ; peristome white, 



reflected, with two teeth on the pillar-lip ; piUar-scale entire Judging fi-oni 



specimens obligingly sent me by ]Mr Millar, I am inclined to consider his 

 Turbo Everetii (Annals of Phil. xix. 377-) as belonging to this species. 



101. C. biplicata. — Whorls twelve or thirteen, aperture en- 

 tire, compressed ; pillar-scale entire. 



Turbo bip. Mont. Test. Brit. 316. t. ii. f. 5 — In Wiltshire. 

 Length about fths of an inch, brown, with distmct lines of growth ; whorls 

 slightly rounded ; aperture narrow at both ends ; peristome entire, detached, 

 slightly reflected, with two approaching teeth on the body-lip. This species, 

 specimens of which were sent me by Mr Montagu, does not seem to corre- 

 spond with any of those described by Draparnaud The Helix papillaris of 



