WHELK, the name given to a large number of marine gas tropod molluscs (see GASTROPODA, MOLLUSCA) with solid spiral shells, and in particular to the members of the genus Buccinum in which the common whelk (Buccinum undatum) is placed. Fusus antiquus, the "hard whelk" of British fishermen, is another common form of whelk. The rock whelks (Murex) and dog whelks (Purpura) are allied forms. All these molluscs are placed in the sub-order Rachiglossa of the streptoneurous Gastropoda and are distinguished by their carnivorous and aggressive habits and the modification of their mouth-parts as an eversible pro boscis. The radula (rasping tongue) is simple as compared with that of the plant-eating gastropods, and consists usually of three large teeth suited for tearing animal tissues. The nervous system is condensed by the approximation of the constituent ganglia and the shortening of the commissures. The eggs are deposited in horny capsules which are usually aggregated in clusters.
The common whelk has a wide distribution in the North At lantic and ranges from the eastern seaboard of North America to the coast of Siberia. On the east side of the Atlantic the
southern limit of its distribution seems to be the south end of the Bay of Biscay. It is found at all depths from low water mark down to about 'co fathoms and on many kinds of bottom. Cer tain varietal forms are said to occur at greater depths. It is a carnivore, eating both living animals and carrion, especially other molluscs, e.g., clams and scallops. Indeed Petersen considers that in Danish waters the whelks prey on the plaice when caught in nets. Danish fishermen have estimated that one-third of the year's catch is lost in this way. In the British Isles the whelk is caught by the use of wicker crab-pots baited with living crabs, by dredging and by "trotting" (line-fishing with crabs tied together as bait).
See W. J. Dakin, "Buccinum," Proc. and Trans. Liverpool Biological Society (1912). (G. C. R.)