The author of Casserole Cookery has netted a fine kettle of shellfish delicacies, most complemented by suggestions for complete menus. Beginning with a selection of clam recipes the author takes on crab, lobster, oysters, scallops, shrimp, mixed sea-food and a fascinating catch of ""miscellaneous shellfish"" --sea urchins, periwinkles, conch and a turtle variety or two. Although the novice cook may initially pale at mention of such special equipment as ""quiche pans"" and ""Swedish pancake pans,"" and wince at the directions for attacking quiescent but still mildly ambulatory crabs, there is such a delightful variety of savory dishes suggested here, and such a range of skills required, that the temptation to try a few is irresistible. The novice will also be glad to note that the inevitable recipe for paella has but seventeen ingredients as opposed to the latest Times epic which requires thirty. Also, the author admits canned and frozen products to many of the dishes including Maryland Crab Soup and both New England and New York clam chowders.