Distinction between Cardium edule L. and Cardium lamarcki Reeve

Abstract

FROM material gathered by the Danish Institute for Fishery and Marine Research in Danish estuaries I have examined the species of Cardium of which there were three types—A, B and C. Type C was identified as C. exiguum. In the literature the types A and B are described as varieties of C. edule. In my material the two types existed together in some of the estuaries, and they were often found in the same bottom samples, and always without any intermediate types. I have identified type A as C. edule L. and type B as C. lamarcki Reeve 18451.