236 



COT^CRYLIA—DITHYRA. 51. 



the support of the inhabitant ; being furnished with two tooth-like 

 processes, originating in the concave surface a little below the 

 hinge, extending inwards towards the margin, and variously branched 

 in various species. 



ranium. Terebratula testd ovatd semipellucidd, striis minutis decussatis, 

 margine interno integerrimo. 

 Shell oval semitransparent, with minute decussate striae, and the 



inner margin very entire. 

 Anomia Cranium. Chnelin, Syst. p. 3347. 



Turton, Linn. Syst. iv. p. 287. 

 Dillwyn, Descript. Catal. p. 294. 

 Turton, Conch. Diet. p. 5. 

 Terebratula Cranium. Montagu, in Linn. Trans, xi. p. 188, tab. 13, 



fig. 2, and B. 

 Dredged in Bressay, in the Shetland Islands, by Dr. Fleming. 



Shell an inch long, and hardly as much broad, convex, thin, 

 brittle, covered with a dull white skin, under which it is milk-white 

 and semitransparent; the surface very finely reticulate or shagreened. 

 The internal projecting processes of the under or shorter valve 

 have a lateral ramification issuing from the base on one side. 



Psittacea. 

 2. 



Terebratula testd ovatd, striis longitudinalihus, umbone preelongo 



curve, margine sinuate integerrime. 

 Shell oval, with longitudinal striae, the beak much produced and 



curved, and the margin sinuous and very entire. 

 Aiiomia Psittacea. Gmelin, Syst p. 2348, 



