1042 PATELLA. 



stream near Folkestone, in Kent, more strongly striated than 

 usual, which were considered as a distinct species." 



OBLONGA. 58. Shell membranaceous, brittle, slight- 

 ly contracted in the middle, with the summit 

 pointed and obliquely reflected; base oblong. 



Patella oblonga. Lightfoof in Phil. Trans. Ixxvi. p. l68. 

 t. 3. f. 1,2, 3, and 5, Donovan, v. t. 150. Maton and 

 Racket, in Lin. Trans, viii. p. 233. Dorset Cat. p. 58, 

 t. 18. f. 20, and t. 22. f. 8 a. 

 Patella piccolissima. Ginanni, Op. Post. ii. p. 50. t. 2. f. 1 1. 

 Patella lacustris. Gmelin, p. 3710. Montagu Test. p. 484, 

 Patella, No. 101. Schroeter Einl. ii. p. 483. 

 Ancylus lacustris. Muller Verm. ii. p. 199. 

 Ancylus fluvialilis. Schroeter Fluss. p. 205. t. 5. f. 4, a 



and b. 

 Guaiter, t. 4. f. AA. 

 Inhabits rivers on aquatic plants, in most parts of Europe. 

 The base is about a quarter of an inch long, and hardly half as 

 broad ; it differs from P. lacustris in being nmch narrower 

 in proportion to the length, and in having the summit smaller^ 

 more central, and obliquely reflected. 



***** With the summit obtuse, and the margin entire. 



PELLifCiDA. 59. Shell convex, membranaceous, 

 pellucid, with about four longitudinal azure 

 rays ; summit obsolete and nearly marginal ; 

 base ovate. 



Patella pellucida. Linnmts S^st. Nat. p. 1260. Pennant 

 Zool. iv. p. 143. t.90. f. 150. Born Mas. p. 424. 1. 18. 

 f. 9. Schroeter Einl. n. p. 423. Chemnitz, x. p. 331. 

 t. 16B. f. l620. Gmelin, p. 3717. Schreibers Conch, i. 

 p. 355. Montagu Test. p. 477 and Supp. p. 153. Dor- 

 set Cat. p. 58. t. 23. f. 5. 



Patella coeruleata. Da Costa Brit. Conch, p. 7. 1. 1. f . 5 

 and 6, 



Patella pellucida, junior. Maton and Racket, in Lin. Trans. 

 viii. p. 233. 



Lister Conch, t. 543. f.27. 

 Inhabits the coasts of Norway, and the Mediterranean. Litt" 



naus. Britain. Lister, S^c, 



