Soft shelled crabs
Clean crabs, sprinkle with salt and pepper, dip in crumbs, egg, and crumbs, fry in deep fat, and drain. Being light they will rise to top of fat, and should be turned while frying. Soft-shell crabs are usually fried.
To Clean a Crab. Lift and fold back the tapering points which are found on each side of the back shell, and remove spongy substance that lies under them. Turn crab on its back, and with a pointed knife remove the small piece at lower part of shell, which terminates in a point; this is called the apron.
Source: Boston Cooking-School Cook Book, 1896