378 Messrs. R. M'Andrew and L. Barrett's List of the Mollusca XXXIII. — List of the Mollusca observed between Drontheim and the North Cape. By R. M'Andrew, Esq., F.L.S., and L. Barrett, Esq., F.G.S. Our observations extended along 700 miles of coast, 300 of which were south and 400 north of the arctic circle, and from the littoral zone to a depth of 200 fathoms. The opportunities for dredging were most favourable, the coast being protected from the Atlantic swell by the numerous islands to the seaward ; and the deeply indented fiords supplying many secure anchorages and sheltered dredging grounds. In the following lists the Norwegian distribution of each species is given, the coast being divided into three provinces, so that the extreme southern limit of the arctic species, and the northern limit of the southern spe-cies, can be more correctly ascertained. Gasteropoda. We met with 103 species of this class ; of these 91 belong to the order Prosobranchiata, and 12 to the Opisthobranchiata. The smaller species were extremely abundant, but the larger species of Buccinum and Fusus were seldom met with. Prosobranchiata. Note. — The figures in the first column of this and the following pages indicate the extent of the range at which the species was met with, whether ahve or dead ; in the second, the greatest and least depth at which it was dredged alive ; in the third, the kind of sea-bottom is named ; in the fourth, the letters express the degree of frequency of occurrence : — a. abundant, generally distributed and plentiful ; /. frequent ; I. local, more or less plen-tiful in a few localities ; r. rare ; and v. r. very rare, when but few ex-amples occurred. In the fifth column the northern Scandinavian distri-bution is given, the coast being divided into three unequal provinces : North Drontheim (Dront.); Nordland (Nord.); and Finmark (Fin.).
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