G30 MOLLUSCA. 



Lingula anatina. — The Duck Lingula. Plate Ixxvi. fig. 7. Green, shaped 

 .ike a duck's bill ; and having a cylindrical pedicle. Four inches long. 

 Inhabits the Indian ocean. 



Terehratula cranium. — The Skull Terebratula. Plate Ixxvi. fig 1. 

 Slightly ovate, veutricose ; summit of the convex valve produced and blunt ; 

 with divergent striae, and the margins crenulated. Half an inch long. 

 Inhabits the sea at the Zetland Islands. 



Crania personata. — The Masked Crania. Plate Ixxvi. fig. 5. Orbicular; 

 the upper valve gibbous and conical ; lower valve flat, with three perfora- 

 tions. Inhabits the Indian ocean. 



Anomia undulata. — The Waved Anomia. Plate Ixxvi. fig. 2. ' Sub. 

 orbicular, pellucid, with strong, irregular, undulated, longitudinal striae, 

 and some transverse concentric striae ; outside yellowish dirty green ; 

 inside fine green ; the ligament perforation large and ovate. Two inches 

 broad. Inhabits the British coasts. 



Placuna placenta. — The Placenta Placuna. Plate Ixxri. fig. 3. Sub- 

 orbicular, flat, white, and pellucid, with fine longitudinal striae, slightly 

 decussated. Four inches long. Inhabits the coasts of China. 



Vulsella lingulata. — The Latchet Vulsella. Plate Ixxvi. fig. 4. Elongated, 

 depressed, transversely striated ; pale yellowish brown, with longitudinal 

 darker stripes. Four inches long. Inhabits the Indian ocean. 



Ostrea edulis. — The Edible Oyster. Plate Ixxvii. fig. 3. Sub.orbicular, 

 rugged, with undulated, imbricated scales, and transversely striated ; one 

 valve flat, and the other convex ; outside brownish-green ; inside pearly- 

 white; exceedingly variable in size. Inhabits the coasts of Europe. 



Gryplusa angulata. — The Aiigulate^^ Gryphaea. Plate Ixxvii. fig. 1. 

 Oblong-ovate, with tliree longitudinal, carinated ribs below; beak large, 

 soraewliat oblique. Four inches long. Habitation unknown. 



Spondylus longispina. — The LongiSpined Spondylus. Plate Ixxvii. fig. 2. 

 Longitudinally sulcated and ribbed, thickly spined ; of a reddish colour ; 

 alternate spines, arcuated and tongue-shaped ; umbones orange. Four 

 inches long. Inhabits the Indian ocean. 



Plicatula ramosa. — The Branched Plicatula. Plate Ixxvii. fig. 4. Oblong, 

 trigonal, very thick ; with strong longitudinal plaits ; brown, or yellowish, 

 brown, with rust-coloured, arrow-shaped markings ; inside white. One 

 inch and a half long. Inhabits the American seas. 



Pecten raria. — The Speckled Pecten. P.ate Ixxvii. fig. 5. Ears very 

 unequal ; with about twelve ribs, covered with transverse, prickly scales, 

 variously clouded and speckled with a variety of colours. Two inches and 

 a quarter long. Inhabits the European seas. 



Plagiostonia spinomm.— The Thorny Plagiostoma. Plate Ixxvii. fig. 6. 

 Sub-arcuated, with the umbo of one shell higher than that of the other, 

 with longitudinal ribs, and remote concentric rings. Fossil. Britain. 



Lima, vitrina. — The filass.y Lima. Plate Ixxvii. fig. 7. Ovate-oblong; 

 extremely pellucid, and pure snowy- white, with longitudinal distinct striiB. 

 One half inch long. Inhabits the British seas. 



Pedum Spondyloideum.— The Spondylus-Shaped Pedum. Plate IxxviL 

 fig. 9. Ovate, wedge-shaped, flat; the superior valve with longitudinal 

 striae, white, rough, and granulated, slightly tinged with purple near tlie 

 beak. Two inches and a half long. Inhabits the Indian ocean. 



Meleagrina Margaritifera.—The Pearl-Bearing Meleagrina. Plats 



