MANGELIA. 469 



continued likewise upon the smaller turns. This colouring 

 is wholly or partially obsolete upon the Zetland examples, 

 which are almost entirely white. In decussated sculpture 

 and rounded whorls it resembles linearis, but the raised 

 spiral strise (occasionally dotted with very short brown 

 lines, but never painted throughout as on that shell) are 

 more numerous, and much closer, as the interval between 

 each of the larger ones is filled up by a finer stria. The 

 ribs, which are often a little oblique, vary considerably in 

 number and projection ; the majority of our native speci- 

 mens having as many as fifteen or sixteen rather depressed 

 costaj on each of the two principal turns, whilst some of the 

 foreign ones are only provided with ten abruptly elevated 

 ones on any volution. The body is more or less ventricose, 

 and occupies quite one half of the total length ; it is more 

 or less gradual in its basal attenuation, and ends in a 

 rather broad beak : the basal declination is well-rounded. 

 The shape of the mouth, which is almost as long as the spire, 

 and ends in a rather open canal, is oval oblong ; near the 

 outer lip, which is prominent and greatly arcuated (in our 

 native specimens it is disposed to expand, and is rarely if 

 ever thickened by an external rib), it is white but occasion- 

 ally is stained further inwards with livid purple : the throat 

 is quite smooth. The labial sinus is small but distinct. 

 The largest example we have ever seen, measured eleven 

 lines in length, and four and a half lines in breadth. 



The animal is white, sometimes slightly tinged with 

 purple. Its tentacula are long and slender, their thickened 

 eye-bearing portions extending for only about a third of 

 their lengths. The foot is very large and expanded, 

 truncated and strongly auriculated in front, produced and 

 pointed behind, exhibiting the appearance of having a 



