444 BULLION. 



creamcolour ; young and half-grown specimens are often 

 adorned with narrow reddish-brown zones, parallel and alter- 

 nating with the white spiral stride and their walls : spire 

 loosely coiled, not exposed in the adult, being coated over by 

 successive deposits from the hinder lobe of the mantle : crown 

 obliquely indented, and encircled by an angular rim; it is 

 perforated in the young and fry, so as to show the outer part 

 of the spii'e : mouth narrow above, and dilated below, with a 

 rounded base ; its length exceeds that of the spire : outer lip 

 not much curved in the middle ; it projects beyond the crown, 

 forming in that part an obtuse angle : inner lip broad and 

 flexuous, consisting of a rather thick glaze : pillar arched, 

 visible throughout by holding the shell upside down. L. 2-33. 

 B. 1-5. 



Yar. 1. alba. White, with a creamcoloar epidermis. 



Yar. 2. curta. Smaller and shorter, but not having the 

 compactly convoluted spire and comparatively small mouth of 

 S. lihrarius. 



Habitat ; All our coasts : it usually frequents the 

 coralline zone, ranging as deep as 90 f. ; but. Dr. Lands- 

 borough says that " at Whiting Bay, in Arran, it may 

 be taken by digging in the sand at ebb tide.^^ The 

 1st variety is generally diffused, but rare. Y^ar 2. 

 Shetland. This species occurs in the quaternary and 

 upper tertiary beds at Belfast (Grainger) ; Greenock 

 (Robertson) ; and tlie Red and Coralline Crag (Wood) ; 

 as well as throughout Belgium, France, Italy, Germany:, 

 and the southern parts of Europe. Its distribution, in 

 a living state, extends from Finmark (Danielssen and. 

 Sars) to Gibraltar (M ^Andrew) _, and through the Medi- 

 terranean, Adriatic, and JEgean; depths 8-60 f. 



This voracious mollusk does not despise any kind of 

 animal food, from minute Foraminifera to the sea-mouse 

 or Aphrodita, the spines of which I found in the gizzard 

 of one individual. Corbula gibba is evidently a favour- 

 ite morsel ; and I have observed Dentalium entalis, 

 Odostomia rufa, smdDiirupa arietina in other specimens. 



