BRITISH MOLLUSCA. 
163 
Mya pictorum, Montagu , T. B. 36; Donov. B . S. 1. 176. 
Unio batavus, Gray, in Turton Man. 2nd ed. 
Inhab. Continent of Europe. Introduced by Dr. Turton as 
British, in mistake. 
36. Unio ovalis. 
Mya ovalis, Mont. T. B. 563 ; Donov. B. S . t. 89. 
Mya ovata, Wood, Conch. 105. 1. 19. f. 5. 
Mysca ovata, Turt. Biv. 246 ; Man. ed. 1. 21. f. 12. 
Unio Batava, Lamk. Hist. v. 78, 2nd ed. vi. 542 ; Pfeiffer , i. t. 5. 
f. 14. 
Young shell elliptical ovate, Pfeiffer, ii. t. 2. f. 23, 
Unio ovalis. Gray, in Turt on’ s Man. 2nd ed. 
Inhab. Continent of Europe. Introduced by Montagu. 
37. Arca Nile? 
Area Nose, Turton, Conch. Diet. 9 ; Brit. Biv. 166 ; Flem. Brit. 
An. 397; Thorpe, Mar. Conch. 101; Poli, Test. Sic. ii. 128. 
t. 24; Desh. Exp. Alger. Moll. t. 120; Mat. fy Back. Linn. 
Trans, viii. 91 ; Forbes Sp Hanley, Brit. Moll. ii. 234 (note). 
Inhab. Mediterranean. Introduced by Dr. Turton. 
38. MYTILUS BIDENS. 
Mytilus bidens, Linn, (not Born nor Dillw.) S. N. ed. 12. 115 ; 
Desh. Lamk . Hist. ed. 2. vii. 39 ; Forbes Sc Hanley, Brit . Moll. 
ii. 178. 
Mytilus striatulus, Schroter, Einleit . Conch, iii. 449. t. 9. f. 16; 
Turt. Mag. Nat. Hist. vii. 350 ; Thorpe, Brit. Mar. Conch. 110; 
Ind. Test. t. 12. f. 19. 
Perna striatula, Betz. Nov. Gen. Test. 21. 
Mytilus exustus, Lamk. (not Born, Gmelin, nor Dillw.) Hist. 2nd 
ed. vii. 39 ; Thorpe, Brit. Mar. Conch. 22 ; Desh. E. M. Vers, 
Supp. ii. 559 ; Hanley, Bee. Shells, i. 244. 
Lister, Hist. Conch, t. 366. f. 206 ; Ency. Meth. Vers, t. 220. 
f.2(?), 3, 4. 
Inhab. W. Indies. Introduced by Dr. Turton, upon the authority 
of Mr. Bean, as having been found by him at Scarborough on 
floating timber. 
a, b. “ Scarborough.” From the Collection of Mr. Bean. 
c — h. Ditto. 
39. Mytilus crenatus. 
Mytilus crenatus, Lamk . Hist. 2nd ed. vii. 38; Willcox, Zool. 
Journ. i. 590 ; Beport Brit. Assoc, iii. ; Sowerby, Linn. Trans . ; 
Gen. Shells, Myt. f. 3 ; Davies Sf Willcox, Ann. Phil. 1825, 
148; Zool. Journ. i. 584; j Reeve, Conch. Icon. t. 102. f. 3; 
