100 MYA. 



This is a new species, for which, with many more, 

 we are indebted to Mr. Montagu, who received it from 

 the Frith of Forth. 



PURPLE GAPER. 



18. Mya purpurea. M. testa ovata, transverse rugosa ; cardinis dente 

 erecto, solitario. 



Shell oval, transversely wrinkled ; hinge with a single erect tooth. 

 Mont. Test. Brit. Suppl. p. 21. Penn. Brit. Zool. 1812. 4. p. 167. 



An oval shell, slightly wrinkled transversely ; of a 

 whitish colour, with a purple beak. There is a single 

 erect tooth, slightly notched, in each valve. 



This is a minute species, not above the twelfth part 

 of an inch long. Discovered amongst corallines on the 

 Devonshire coast, by Mr. Montagu. 



RUSTY GAPER. 



19. Mya ferruginosa. M. Testa subovali, obsolete rugosa ; cardinis den- 

 tibus duobus porrectis. 



Shell somewhat oval, with obsolete wrinkles ; hinge with two projecting 



teeth. 

 Mont . Test. Brit. Suppl. p. 22. t. 26. f. 2. Penn. Brit. Zool. 1812. 



p. 167. 



The beak of this shell is obtuse, and placed nearest 

 to one end ; the colour is white, but the shell is usually 

 covered with a rusty coat which is thick and tenacious. 

 The inside is white, and the hinge has two projecting 

 teeth, separated by a large triangular notch. 



This shell was found on Belton Sand, near Dunbar, 

 in Scotland, and is about a quarter of an inch long, 

 and nearly twice as broad. 



