Shell and devein. Shell and devein. Three little words in a shrimp recipe which signal a rather tedious job is ahead. But is that step really necessary?

Cookery expert James Beard's shrimp recipes call for shelling and deveining. Personally, he thinks shrimp have a more delicate flavor, and are less gritty when they're deveined. But he says it really isn't necessary.

Loni Kuhn, San Francisco cooking school teacher, recently answered a student who wanted to know if she really had to devein shrimp:

"Only if you're terribly fastidious. But if you're lazy and practical like me you won't bother. Shrimp don't eat anything we don't, and deveining the little devils is one of the most boring jobs in the world."

Actually, shrimp do eat a few things we don't, such as their own shells, sand, mud and seaweed. But the point has been made.

Even restaurants are beginning to skip this job. If you want them deveined, you have to do it yourself, even at 50 cents a shrimp. The chef at one resutarant said no one had complained.

Dr. Isabelle Canet, crustacea expert at the Smithsonian Institution, says the vein is harmless, but she is "100 per cent in favor of cleaning them . . . they are more attractive.

What it seems to boil down to is that hygienically it isn't necessary; esthetically, it's nicer.

Since it has been a good year for shrimp you may want to be serving more of them.

Supplies are plentiful, and prices are running just a shade lower than than year in some markets, not all. Giant Food has had specials on large shrimp at $3.99 a pound, but the price is hovering at about $5 per pound at most seafood markets for the 36/40 to the pound size.

The Giant Food specials have had another purpose - to lure customers back to eating shrimp. Karl Hooker, Giant seafood buyer, says that five years ago when Giant began posting "Fresh" and "Previously Frozen" signs with its seafood products shrimp sales dropped by more than half when they added the "Frozen" sign.

"It's a shame that people are denying themselves the same product they previously enjoyed," he says. "We went out of the fresh shrimp business in 1952."

Even with a price drop, shrimp are still pretty much in the special occasion and dinner party category. Here are three party shrimp recipes where the shrimp shells are left on and the guests have to do part of the work. But it's like cracking a lobster claw or sorting through mussel and clam shells looking for a morsel, and it makes dinner more interesting. SHRIMP WITH PINE NEEDLES (Six servings as an appetizer) 1 pound medium shrimp, unshelled, washed 1/4 cup lemon juice 1/4 cup soy sauce Green pine needles, washed Rock salt

Place a half-inch layer of rock salt in a shallow or ovenproof baking dish. Heat dish at 350 degrees for 15 minutes. Remove from oven, scatter a few pine needles on the hot salt, arrange shrimp on pine needles. Use a lid or aluminum foil and cover tightly. Return to oven for 10 to 15 minutes, or until shrimp are pink and cooked. Serve in baking dish and garnish with fresh sprays of green pine needles. Mix lemon juice and soy sauce in equal parts and serve in individual sauce dishes. PARMESAN STUFFED SHRIMP (Serves six) 30 shrimp (16/20 size) unshelled, washed 1 1/2 cups olive oil 3/4 cup lemon juice 1 clove garlic 1/4 teaspoon salt 2 cups fine bread crumbs 3/4 cup parmesan cheese, grated 2 teaspoons dry sherry Chopped parsley for garnish

Make marinade of oil, lemon juice, garlic and salt. Split raw shrimp down the back, but do not peel. Devein shrimp (because they're large) and split part way through. Marinate shrimp 30 minutes or longer. Combine parmesan and bread crumbs. Add sherry and moisten with some of the marinade. Fill split shrimp allowing about 2 tablespoons of stuffing for each shrimp. Place in neat rows in shallow baking apn and sprinkle with lemon juice. Bake at 350 degrees for 20 minutes. Serve with a sprinkle of fresh, chopped parsley. (This dish can be made in the morning and refrigerated before cooking. Add an extra 10 minutes cooking time to take off the chill.) SMOKY BROILED SHRIMP (8 servings as an appetizer) 2 pounds medium shrimp 1/2 cup salad oil 2 cloves garlic, crushed 1 tablespoon lemon juice 1 tablespoon liquid smoke 1 teaspoon salt

Split shrimp shells down the back, but do not shell or devein. Make marinade of remaining ingredients. Marinate shrimp 2 or 3 hours. Broil in rack or on skewers over coals about 5 minutes, turning once, and basting with marinade.