These crabs are very plentiful in certain Virginia oysters. Boil some vinegar, season it with salt, whole peppers, spices, mace, cloves and bay leaf, throw the crabs into this vinegar with an equal quantity of oyster liquor, skim it carefully and remove it at the first boil, then set it away in bottles and keep them in a cool place. Serve on side dishes with slices of lemon around, and a little of their own pickle poured over.
This is a shellfish preserve made without any measured acidity, sterilisation or refrigeration, and it cannot be reproduced safely. The notes below explain the specific failures rather than offering a corrected method.
Charles Ranhofer compiled The Epicurean (1894) from his decades as chef at Delmonico's in New York, and oyster crabs belonged squarely to that world: a luxury that cost nothing but labour, since they arrived free inside barrels of Chesapeake and Virginia oysters and had to be picked out one at a time. Nineteenth-century American menus treated them as a delicacy in their own right, usually deep-fried in a heap with whitebait, occasionally in a cream stew, and here soused in spiced vinegar. The pickling itself follows the standard European fish-souse pattern of the period, with mace, cloves and bay in boiling vinegar, and it reflects a kitchen that relied on cool cellars and a fast turnover rather than on any understanding of what acidity actually does. Pea crabs are still legal to eat and still show up occasionally in an oyster today; the industrial shucking that once made them available at all is what has gone.