In a short communication Grahame et al. (1992) argue against our finding that Littorina neglecta Bean is an ecotype of Littorina saxatilis (Olivi) rather than a separate species (Johannesson & Johannesson, 1990b). Unfortunately, Grahame et al. (1992) have miss-represented our earlier paper, and we feel the need to refute their arguments.

In populations from north-western Europe we studied morphological characters used to separate Littorina neglecta from L. saxatilis. We found that intermediate shapes were common and, furthermore, we found no close coupling among characters used to define L. neglecta (Johannesson & Johannesson, 1990a). We further analysed the genetic variation in five strongly polymorphic allozyme loci. In four loci we found a pattern that indicated that L. neglecta is not reproductively isolated from L. saxatilis. In the fifth locus, Aat-1, we found consistent differences between populations of L. neglecta (from the low shore) and L. saxatilis (from the high shore). Similar differences were observed between low and high shore populations in Sweden where, however, no snails of neglecta-type were present.