OF MERGUI AND ITS ARCHIPELAGO. 



205 



298. Pinna (Cyrtopinna) madida, Reeve, I.e. xi.pl.xvii. fig. 31. 

 Elphinstone Island. Port Essington. 



The last three species are very near to one another. 



Mttilid^:. 



299. Mttilus yiridis, L. 



Mytilus smaragdimis, Chemnitz, viii. figs. 745, 746 ; Reeve, I. c. x. fig. 28. 

 Mergui ; King Island ; Sullivan Island. Tranquebar, Ceylon, 

 Singapore, Siam, Borneo. 



300. Mttiltjs (Aulacomya) curvatus, Bunker, Reeve, I. c. x. 

 pi. xi. fig. 53. (PI. XVI. fig. 4, a-d.) 



Varies considerably in outline in the same locality, some spe- 

 cimens being rather straight, others distinctly curved in different 

 degrees. The curvature is probably caused by the position of 

 the individual shell between its neighbours or other objects. 



Crow Islet between King Island and Hayes Island, beneath 

 stones at highest water-level ; Elphinstone Island. Phi- 

 lippines. 



301. Mytilus (Septifer) biloctjlaris, L., Chemnitz, viii. 

 figs. 736, 737. 



Mytilus nicobaricus, Reeve, I. c. x. pi. ix. fig. 42. 

 Bluish green inside. 



King Island ; Elphinstone Island ; Owen Island, coral-bur- 

 rows. Red Sea, Mauritius, Ceylon, Nicobars, Salang, Singapore, 

 Australia, Japan. 



302. Mytilus (Septiyvk) j£xcisxJ8,Wiegmann,Archivf.N'atur- 

 geschiclite, 1837, p. 49 (Tichogonia) ; Reeve, I. c. x. pi. iv. fig. 13. 



Septifer fuscus, Recluz, Revue Zool. 1848. 



Iuside dark purple and w T hite. 



Owen Island. Mauritius, Mozambique. 



303. Mytilus (? Septifer) Andersoni, sp. n. (PI. XVI. fig. 5.) 

 Testa rhombeo-trigona, prseter strias incrementi laevis, nitida, 

 olivacea ; intus olivacea ; marginis dorsalis pars tertia anterior 

 valde ascendens, fere rectilinea, reliquum rotundatum, sensim 

 descendens ; margo ventralis fere horizontalis rectilineus ; facies 

 ventralis paulum concava, angulo tumido sat distincto circum- 

 scripta ; septum simplex, margine libero leviter concavo, appen- 

 dice nulla. Long. 16, alt. 9, crass. 8 millim. 



The locality of this apparently new species is distinctly stated 



17* 



