SUPPLEMENT. 183 



P. 311, 1. 3 from top, for " costatus" r. " sulcatus." 



P. 311. — ASTAKTE SULCATA. 



Body yellowish or pale orange, with a tinge of fleshcolour : 

 mantle slightly grooved lengthwise at the edges, which are 

 thickened and plain ; there are a few small white tubercles at 

 the posterior side : foot tongue-shaped, pale yellow : gills deli- 

 cately pectinated. 



Typical. N, of Hebr., 170-550 f. (C. and T.). F. Norway 

 (Sars and others); Antwerp Crag (Nyst) ; Messina (Seguenza) ! 

 E. Loffoden I., 300 f. (Sars) ; Hveen, Denmark (CErsted) ; 

 Cherbourg (Eecluz). Yar. Scotica. F. Norway (Sars). E. 

 Loffoden I., 250 f. (Sars) ; Brittany (Recluz) ; Toulon (Sou- 

 leyet). Yar. elliptica. F. Scandinavia, Canada, and U. S. 

 E. Labrador (Packard). A form intermediate between this 

 variety and the type has been found in a fossil state at Belfast 

 by Mr. A. Bell, and living in the Faroe Isles by Sysselman 

 Miiller. Yar. incrassata. F. N.W. Germany (Philippi); Italy 

 (Brocchi and others). 



P. 315. — A. COMPRESSA. 



Body yellowish or pale orange : mantle slightly lineated to- 

 wards the edges, wmich are thickened, of a darker hue, and 

 minutely tuberculated on the posterior side: foot tongue- 

 shaped, yellowish-brown. 



E. Vancouver's I. (P. Carpenter, as A. compacta). Yar. 

 globosa. Jf. of Hebr., 530 f. (C. and T.). F., with var. striata, 

 Siberia, Labrador, Canada, and U. S. This species is Venus 

 Montagui, Dillwyn. 



P. 318. — A. triangularis. F. Antwerp Crag (Nyst, as A. 

 minuta) ; N.W. Germany (Philippi, as A. laevigata) ; Monte 

 Mario (Conti, as Cyclina undata) ! E. Brittany (Recluz) ; 

 Loire-Inferieure (Cailliaud) ! 



P. 319. — A. crebricostata. N. of Hebr., 550 f., in "cold area" 

 (C. and T.). F. Gardiner, Maine co. (Lyell). A. Warliami, 

 Hancock. 



P. 320. — A. borealis. F. Greenland, Scandinavia, and N.E. 

 America. 



P. 322. — Ctrce minima. F. Antwerp Crag (Nyst, as Cg- 

 therea trigona); Italy (Calcara and others). E. Bergen (Sars) ; 



