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 CRUSTACEANS records claim only one. An excellent guide to Hunstanton and its Neighbourhood, by Philip Wilson, seventh edition, revised and greatly enlarged, etc., by George Webster, 1881, in the copious natural history, though it speaks of ' the crab-sea,' mentions no crab, and only one solitary crustacean. This is entered under the heading of conchology, and named 'Common Acorn-shell {Lepas balanus).' The account given of it is w^orth quoting : ' Very abundant on the large boulders of black rock scattered along the shore. The little animal inhabiting this multi- valve will afford the observer a spectacle of great interest. Let him find one of these acorn-shells on a small detached piece of rock, and keep it from moisture for an hour or so, till it becomes perfectly dry ; then place it in a basin of sea vv^ater, when it will open the valves of its abode and exhibit its beautiful plume-like processes ; these are the tentacula of the animal, with which it procures its food, and which it waves backwards and forwards in a most graceful manner.' ^ All this is much to the purpose for those who wish to be amused by a pleasing sight, and do not care to be troubled with scientific technicalities. But it is strange that in 188 1 a writer on natural history should still be classifying the crustacean cirripedes among the Mollusca. It is equally strange that one of Charles Darwin's fellow-countrymen should at that date be placidly using such a name as Lepas balanus to distinguish a sessile cirripede species. As most naturalists are perfectly well aware, Darwin devoted several laborious years to the elucidation of this group, and wrote a monograph upon it in two large volumes, published by the Ray Society, one volume describing the Balanidae, the other the Lepadidse. The most casual glance into this standard work would have saved the situation for the Hunstanton Guide. The trivial name of acorn-shell unluckily has been applied to members of both families, but species of Lepas are easily distinguished by their leathery stalk from species of Balanus, which have no stalk, but are firmly seated on the rock or other basis of support. It is evidently not to a Lepas but to one or other of the rock-coating species of Balanus that the Guide refers. The plumose tentacula spoken of are in fact the animal's legs, their waving hairs producing an appearance of ringlets {cirri), from which the name of Cirripedia is derived. The more recent alternative name, Thyrostraca, or door-shells, refers to the valves, the opening and shutting of which for emission or withdrawal of the cirri is an attractive sight to every new observer. Faunistic catalogues for areas that are not exceptional are not always highly prized by working naturalists, but the great forest of sea- weed which Frank Buckland speaks of as existing off the north coast of the county might well be made the subject of special exploration. Almost certainly in skilful hands it would largely extend our knowledge of the marine Crustacea of Norfolk. 199
 * Hunstanton Guide, p. 68.