PLATE XV. 
Fig. 1. MACTRA glauca. 
Mactra glauca, Mont. Test. Brit. p. 571. — Bromn in Ency. Brit. vi. p. 410. 
Mactra helvacea. Lam. Syst. v. p. 473. 
Fig 2. MACTRA stultorum. 
Mactra stultorum. Lam. Syst. v. p. 474. — Mont. Test. Brit. p. 94. — Brown in Ency. Brit. vi. p. 410. 
Fig. 3, 4. MACTRA solida. 
Mactra solida. Lam. Syst. v. p. 477 Mont. Test. Brit. p. 92. — Brown in Ency. Brit. vi. p. 410. 
Fig. 6. MACTRA elliptica. 
Mactra elliptica. Brown's MSS — A new species, common in the Firth of Forth, and has been confounded with 
the young of the M. solida, found plentifully alive at Cramond Island. 
Fig. 10. MACTRA striata. 
Mactra striata, Brotvn's MSS. — A new species, found in Loch Strangford, county of Down, Ireland In Lady 
Jardine's Cabinet. 
Fig. 11, 12. MACTRA triangulata. 
Mactra triangulata, Brown's MSS. — A new species, found at Seaton, by W. C. Trevelyan, Esq. and in the Cabinet 
at Wallington. 
Fig. 5. MACTRA truncata. 
Mactra truncata, Mont. Test. Brit. Sup. p. 34. — Brown in Ency. Brit. vi. p. 410. 
Fig. 7. MACTRA subtruncata. 
Mactra subtruncata, Mont. Test. Brit. p. 93. — Brown in Ency. Brit. vi. p. 410. 
Fig. 8, 9. MACTRA dealbata. 
Mactra dealbata, Mont. Test. Brit. p. 95, t. 5, fig. 1. — Linn. Trans, viii. p. 68, pi. 1, fig. 10. 
