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 ZOOLOGY MARINE ZOOLOGY The unique geographical position of Cornwall as the most southerly as well as the most westerly county in England, and the consequently genial temperature of its waters, its form as a long irregular wedge projecting out into the Atlantic, its two hundred and fifty miles of much indented coast line and the possession of the largest amount of southern 'sea frontage' of all the Channel counties naturally create the highest expectations as to the richness and variety of the marine life in its coastal waters. In spite of the barren character of almost the whole of the north coast with its long sea walls of seamed and fissured cliff and its desolate surf-beaten beaches, first expectations are more than realized in the wealth of species not only in the large sheets of enclosed and sheltered sea like Mount's Bay, Falmouth Bay, Mevagissey and St. Austell Bay and Plymouth Sound and the many land- locked coves and tidal estuaries, but also in the long stretches of coastal waters exposed to the full force of the Atlantic storms. To the great variety of littoral and of sea bottom as well as of exposure are due that delight- ful diversity of fauna that makes both shore hunting and dredging along this southern coast so full of interest. Fine sand, coarse sand, friable shales, slate rock and granite are all abundantly represented in the happy hunting ground between tide-marks, and on many parts of the coast rock pools are plentiful. The rocks are in places densely covered with Fucus, Pehetia, and other brown sea-weeds, frequently arranged in definite zones, and the cracks, crevices, and overhanging ledges of the rocks themselves are often thickly tenanted. The characteristic laminarian and coralline zones are in places extensively developed, and the zostera beds occasionally yield an exciting harvest. In deeper water shell sand alternates with gravel and with stones, and there is in places an admixture of mud with the former. Many of the trawling grounds contain a rich and varied population, which is naturally increased by the frequent patchy character of their deposits. Though the difficulties of dredging on some of the stony bottoms are at times consider- able, the results on the average are more than proportionate to the trouble involved. The richness of the Cornish marine fauna has naturally attracted a large number of enthusiastic local observers, as well as many eminent naturalists from without. Jonathan Couch of Polperro, his son Richard i 113 15