The English in our period were quite fond of seafood. My period cookbooks have recipes for such things as smoked fish soup, mackerel pie, fried anchovies, collared eel, and even boiled crayfish (yes, they have crayfish in England). You don’t find recipes for periwinkles and whelks because they were common food for the common people. But they’re mentioned in the famous cookbook by Mrs. Beeton (1861), where she has a table of how much seafood of every type was sold that year in London. Apparently, Londoners ate 4 million whelks (compared to half a million crabs and a million lobsters) and an astonishing 304 million periwinkles!

Turtle soup was common on menus in England going back to before the Regency. It had to always be included as a dish for the Lord Mayor’s Banquet in London, and was so popular (and so expensive) that the English even developed Mock Turtle Soup for those who couldn’t afford turtle meat. Mock turtle soup was traditionally made with a calf’s head, so if the idea of eating turtle makes you gag, you might like the mock version even less. Personally, having eaten plenty of it in New Orleans, I enjoy the real thing.