276 MOLLUSCA. PULMONIFERA. Physa. 



2. L. minima. — Elongated, smooth ; volutions rather convex ; aperture less 

 than half the length of the shell, ovate ; last whorl not ventricose. Sower. 

 Min. Conch, tah. 1G9, f. 1. — Fresh water formation. Isle of Wight. 



3. L. longiscata. — Elongated, smooth ; aperture ovate, elongated ; two-fifths 

 the length of the sheU ; plait upon the columella obscure, Sower. Min. Conch, 

 tab. 343. — Upper fresh water formation, Headon Hill. 



4. L. maxima. — Ovate elongated, rather obtuse ; whorls about six, slight- 

 ly concave ; aperture narrow, occupying less than half the length of the shell. 

 Sower. Min. Conch, tab. 538. f. 1. — Fresh water formation, Isle of Wight. 



5. L. columellaris Ovate pointed ; spire short ; whorls about 5, convex ; 



aperture wide, above half the length of the shell ; columella much twisted, 

 and verv thick, Sower. Min. Conch, tab. 528, £ 2. — Fresh water strata, Hord- 

 weU Cliff. 



G. L. pyramidalis. — Ovate acute ; whorls convex ; aperture half as long as 

 the shell, dUated ; plait of the pillar obscurely divided. Sower. Min. Conch, 

 tab. 528, f. 3. — In the fresh water formation of Headon Hill, Isle of Wight. 



Gen. XXX. PHYSA. — Shell convoluted ; aperture longitu- 

 dinal ; peristome wanting in the body-whorl ; margin of the 

 cloak loose, divided into lobes, and capable of being reflect- 

 ed over the surface of the shell, near the mouth. 



116. P.Jxmtmalis. — Whorls four, increasing suddenly from 



thb apex to the body-whorl, which is very large. 



Buccinum exiguum. List. An. Ang. 142. Conch, lab. 134, f. 34 — Pla- 

 norbis Bulla, Mull. Verm. ii. 167 — BuUa fontinalis, Limu Syst. i. 

 1185. Mont. Test. Brit. 226 — Ph. font. Brap. MoU. 54.— Common 

 in lakes and slow running streams. 



Length about half an inch ; pellucid, glossy, horn-coloured, with minute 

 lines of growth ; whorls rounded ; aperture narrow behind ; the body-whorl 

 projectmg. Animal pale dusky yeUow ; an interesting object when viewed 

 crawling against the surface of the water, and extending its delicate, trans- 

 parent, divided cloak over the surface of the shell. The P. alba of Dr Tur- 

 ton, Zool. Journ. vol. ii. p. 363. t. xiii. f. 3, does not appear to be distinct. 



Gen. XXXI. APLEXA. — Shell convoluted; peristome en- 

 tire ; piUar-lip with a fold ; margin of the cloak entire, and 

 incapable of being reflected over the shell. 



117. A. hypnorum. — Spire lengthened ; aperture rounded an- 

 teally. 



Bucc. heterostrophori. List. Conch, tab. 1059, f. 5 — Planorbis turritus. 



Mull. Verm. Hist. ii. 169 — Bulla hypnon Linn. Syst. i. 1185. — Turbo 



stagnalis," Walk. Test. Min. 15. tab. ii. f. 54,— Bulla hypl Mont. Test 



Brit. 228 — Not uncommon in lakes and slow running streams. 



Length upwards of half an inch, deep horn-colour, glossy, translucent ; 



whorls four or five, rather flat, the last one occupying two-thirds of its whole 



length ; aperture narrow behind, the outer-lip nearly straight ; pillar-lip thick, 



rel^^cted, 



