PLATE XXIX. 
Fig. 1. MODIOLA papuana. 
MoDioLA papuana. Lam. Syst. v. p. 111. 
Mytilus modiolus. Moid. Test. Brit. p. 163 — Brown in Ency. Brit. vi. p. 423. — Turton's Brit. Fauna, p. 164. 
Fig. 2. MODIOLA papuana. The young shell. 
Mytilus curtus, Penn. Brit. Zool. pi. 64, f. 76, A. 
Mytilus barbatus, Mont. Test. Brit. p. 161. 
Fig. 5, 6. MODIOLA radiata. 
MoDiOLA radiata, Brown's IMSS. — A new species, found in Cornwall by W. C. Trevelyan, Esq. Jun. of Walling- 
ton, Northumberland, and in the splendid cabinet there. 
Fig. 3, 4. MODIOLA papuana. A distorted variety. 
Mytilus umbilicatus, Donov. Brit. Sh. ii. p. 40 — Mo?it. Te.st. Brit. p. 164. 
Fig. 7. MODIOLA Gibsii. 
MoDiOLA Gibsii, Leach's Zool. Miscel. pi. 98. 
Fig. 8. MODIOLA discrepans. 
MoDiOLA discrepans. Lam. Syst. v. p. 114. 
Mytilus discrepans, Mont. Test. Brit. p. 169 — Brown in Ency. Brit. vi. p. 424. 
Fig. 10. MODIOLA discors. 
MoDioLA discors. Lam. Syst. v. p. 114. 
Mytilus discors, Mont. Test. Brit. p. 167 — Brown in Ency. Brit. vi. p. 424. 
Fig. 9. MODIOLA Prideauxiana. 
MoDioLA Prideauxiana, Leach's Zool. Miscel. 
Fig. 11. MYTILUS EDULis. 
Mytilus edulis, Mont. Test. Brit. p. 159. — Brown in Ency. Brit. vi. p. 423.-^Z,rtw. Sy.H. vi. p. 126. 
Fig. 13. MYTILUS pellucidus. 
Mytilus pellucidus, Mont. Test. Brit. p. 160 — Brown in Ency. Brit. vi. p. 423. 
Fig. 14, 15. MYTILUS elegans. 
Mytilus elegans. Leach's MSS A new species, from the Bell Rock, Firth of Forth. Discovered by my inge- 
nious friend, Robert Stevenson, Esq. Civil Engineer. 
Fig. 12. MYTILUS incurvatus. 
Mytilus incurvatus, Mont. Test. Brit. p. 160 Brown in Ency. Brit. vi. p. 423. 
