The Devon Seafood Grill makes a successful leap from fern bar to handsome fish house

There is a wide selection of fresh seafood (eight separate fish recently), a raw bar, lobsters and a few steaks, and most of it is prepared fairly simply.

There are a few contemporary Asian touches to keep the fare up-to-date - panko-crusted shrimp, mango tartar, Hunan dipping sauces, etc. But Devon, where big-portion seafood entrees hover between $18 and $24, was never really meant to compete with gourmet creativity of the likes of Striped Bass.

Set it rather against the field of nearly half-a-dozen other midrange seafood places that have opened recently, including Bass owner Neil Stein's Fishmarket up the street, and Devon does quite well. Its wine list is affordable, with several wines by the glass, and its space is democratically large, big enough to absorb a crowd.

The dining room is thoughtfully designed, with vaulted brick ceilings (a la Oyster Bar in N.Y.'s Grand Central Station) for better sound, gracious armchairs and two-toned banquets for comfort, wood-partitioned nooks and focused lighting to give the wide space intimacy. Only the table coverings struck me as odd: The crinkly laminated paper reminded me of a giant dentist-office bib.

Judging from the massive crowds that swarm through its open front windows and around the lively bar, where steamer pots send off the aroma of mussels, clams and garlic, the relaxed atmosphere has tapped a responsive niche on Rittenhouse Square. Just down the block, where the Sheraton Hotel seems to have misfired too high, the ambitious little Square Bar is by comparison eerily empty.

Although service has much improved since the opening, it remains Devon's biggest weakness. Our servers were always pleasant, but there were times when they seemed painfully disorganized and slow, unable to maintain a basic flow of the meal.

The kitchen also had a few moments when it could have used a little more finesse. Scoops of jasmine rice were frequently overcooked to mush. The tomato broth of our cioppino stew was oversweet. The shrimp scampi was oppressively rich. And spicy hot peppers, on more than a couple occasions, overpowered other flavors on the plate.

The steamer-pot mussel specials were fine (and a good food value), but lacked a certain oomph, relying too much on softening cream or butter when more edge from a garlicky broth would have given them the appropriate bistro punch.

But mostly, our meals were quite enjoyable, prepared with a consistency worth building upon. The calamari were crisp and tender, paired with a few racy rounds of fried jalapeno peppers. Ginger shrimp made a delicious appetizer, nicely fried and served with a soy and plum wine dip. The seared Hunan scallops benefited from a similar Asian sauce, although it was a little on the spicy side.

Our lobster bisque could have used more crustacean meat in it, but the other soups were wholesome and hearty. The New England chowder was filled with fresh clams, snappy potatoes and bacon. The spicy Creole gumbo was thick (and served with too much mushy rice), but it also had a nice flavor, tinted with authentic sassafras file. And though we found the Caesar dressing slightly goopy, the salad itself was generous, zesty and appealingly fresh.

Most of our fish were cooked just right - Chilean sea bass in a subtle butter sauce; moist swordfish topped with sauteed mushrooms; flaky halibut in a buttery zinfandel reduction with roasted vegetables; ahi tuna perfectly rare. Only the Dover sole was a letdown, awkwardly fileted tableside and a bit too ordinary in flavor for $29.

Lobsters, it seems, are expensive everywhere in town, and Devon's large 2-pounder for $39 was no exception (the 5-pounder at $70, on the other hand, is a relative deal.) I had no quibbles with its preparation, though; it was steamed to juicy perfection and served with sweet white corn and roasted potatoes.

Devon's fine desserts lean toward comfort classics that fit the spirit of the meal. The chocolate mousse cake was light and appealing. Carrot cake was dense and nutty. Swirl-topped cheesecake was smooth and creamy. Key lime pie was generous and snappy. Even the seasonal berries were satisfyingly turned, served in a cloud of whipped cream that whispered Grand Marnier.

Ironically, the house signature apple crumble didn't quite come off. Its bed of nicely spiced apples was not fully heated, while its crumbly crown was a little charred in spots.

And there was something else. I'm irked by one feature of Devon's dessert tray. For display, the scoop of "ice cream" that perches atop the apple crumble is actually a ball of unmeltable Crisco standing in for the real thing.

If I were a cynic, it could be a perfect metaphor for Mr. Potato Skins' gambit to fool us into mistaking yet another fern-bar chain for a decent restaurant.

But after my meals here, I'm convinced that Devon is the authentic item. When my crumble finally came, a ball of old-fashioned vanilla was melting a la mode. To my relief and pleasure, not only was it real, it was Bassett's - good and local.

Craig LaBan's e-mail address is claban@phillynews.com.