Open Monday through Friday, 11:30 a.m. to 2:30 p.m. and 5 to 10:30 p.m.; Saturday, 5 to 10:30 p.m. AE, CB, MC, V. Reservations.

Food: High quality meat and seafood that gets lost in the shuffle

Style: Baronial flourishes only skin deep

Price: Dinner entrees $6.50 to $14; a good meat-and-potatoes meal for $15

WITH THOUSANDS of restaurants scattered through this metropolitan area, it is all too easy to miss good ones, to dismiss some of the best without even trying them, to ignore delicious possibilities. So a restaurant critic looks for sources. Restaurant fans write in their discoveries. Proprietors send copies of their menus. Friends and acquaintances put their notepads at the critic's disposal. And the critic asks - everybody. A cab driver says he's been driving a lot of people to a new Chinese restaurant. A telephone operator reports on yesterday's lunch before releasing a long distance line. In the elevator, in line at the movies, on the way into or out of a restaurant, a critic overhears or is told directly about where people have eaten. But, insatiable, I sometimes go to professionals to ask them. And sometimes (rarely, but often enough to consider the chase worthwhile) I come up with a surprise.

That's how I got around to James 111. I asked a seafood dealer and a meat wholesaler if they knew of any unsung heroes among restaurants, unexpected places which ordered nothing but the best meat and fish. Both named James 111. And both added that the prices were reasonable for the quality.

Three visits later I both agree and disagree that James 111 is an unsung hero.

What James 111 primarily illustrates is how many opportunities a restaurant has for fumbling. It is true that the quality of the meat is fine. The steak is full-flavored and well butchered, broiled to a crusty exterior, through mine was removed from the fire slightly too late to accomodate a taste for rare meat. The veal is pale and perfect, served either simply francais or sauteed in an egg batter and weighted with excellent crabment, but unfortunately blemished by canned asparagus and a bare hint of bearnaise sauce. But the sleeper on the menu is the rack of lamb - served for one person but its seven tiny ribs are enough for a pair - cooked rare and lightly flecked with parsley. First on the menu is roast prime ribs, but on a half-empty weekday it was already sold out by 8 P.m., so for most diners that evening (including me) its quality was irrelevent.

Seafood, too, obviously starts with good heritage, but too often fritters it away. Few other places in Washington still serve oysters or clams on the half shell for $1.95, and even at twice the price they are rarely as large and briny-fresh. But from the same kitchen issues a clam chowder which has only a passing acquaintance with clams, and cooked clams that sway unpredictably from fragrant, delicious clams casino to bland clams florentine lost under a dense cream sauce and tasting far more of spinach than of clams. For oceanic main dishes, the crab imperial lives up to its promise, being sweet lumps of backfin crab - not picked quite enough, but generously portioned and lightly tossed with bits of pimiento, glazed to a golden crust. Fish filets - rockfish and, some days, salmon, trout and the like - suffer the fate of the steak, being cooked just past the juiciest point. Again, the care in purchasing is undermined by careless preparation, and the more ambitious the dish the greater the flaws. Duck bigarade, besides being misspelled on the menu, is misguidedlyy sauced with a sweet, starchy concoction that masks neither the burned skin nor the fatty interior.

If this were a simple steak house, it would fill a hunger rarely well attended in Washington. But it reaches for a splendor well beyond its grasp. In a Hollywood musical version of Olde England complete with crowns suspended from the ceiling and an overdose of stained glass, velvet draperies, pewter and Renaissance red, the awkward service takes on comic proportions. Water and wine are withheld long past their need. Lacking a bell to summon a servant, one is tempted to shout for help. Attempts at grandeur turn out to be delusions, from parisienne potatoes in reality canned, to the salad a watery iceberg background for sugary dressings. Gold foil does not a baked potato make, and warm loaves of slice-it-yourself bread don't rise above their squashy texture. One flinches at snails -delicious as they are - served in ceramic pots, yet accompanied by irrelevant shell tongs. As perfunctory - though modestly priced - as the wine list is, one squirms to find chablis listed under the reds. In true steak-houses one usually finds only a couple of simple desserts available; here the menu lists four times that many.

It is as if humble virtue was scorned for a facade of sophistication. James 111 takes off into flights of fancy where it should stay on the ground tending its fire. A good, big piece of beef at $8 to $9 is enough of an excuse for its existence. And a dinner of impeccable oysters and rack of lamb with a drink or a simple wine for about $15 is enough cause for celebration. Alas that there is much underbrush to thrash through in order to enjoy it.