They are border crossers, quietly arriving in everlarger numbers, yet hardly noticed. I’m talking wines here, not people, and the border in question is northern. And the migrants are the increasingly worthy wines of Canada.

A top tier sampling of these wines, red and white, dry and sweet, accompanied a recent dinner at the Modern, hosted by the counsel general of Canada. The evening’s sommelier, Canadian-born Paul Grieco of Hearth restaurant on 12th Street, opened with his native land’s strong suit: riesling.This one was the Cave Spring Reserve Riesling 2003, Niagara Peninsula. “I’m an acid hound when it comes to wine,” Mr. Grieco said, and this example was a live wire in the glass. Its barely off-dry, mineral and petrol inflected flavors synergized brilliantly with Nova Scotia scallops marinated with basil oil, strawberry juice, and rhubarb mousse, an otherwise daunting dish with which to pair a wine. “The best result is when you have two things and you create a third thing,” Mr.Grieco said. Here, the result was pure scintillation.

Asparagus can ambush wine, and in the next course it did just that to Peninsula Ridge Sauvignon Blanc 2004.A pleasing but low-key wine on its own, it was neutralized by Ontario white asparagus and gribiche sauce. But the richer, oilier, Jackson-Triggs Sauvignon Blanc Reserve 2003, Okanagan Valley, managed to harmonize with the same dish. Mr. Grieco nailed the key quality of the wine as “that cat pee thing that put up a kind of bass line around the asparagus.” This is one sommelier who tells it like it is.

One step up in richness came with the pair of wines served with Nova Scotia lobster in a jar with young warm vegetables. Both were from Niagara Peninsula, a region that is moderated in the critical post-summer ripening season by the still-warm waters of Lake Ontario. First came the vanilla-scented, big-bodied Cave Spring Reserve Chardonnay 2003.Then Stratus White 2002, a forceful medley of chardonnay, sauvignon blanc, riesling, and semillion. All these whites were animated with foodfriendly acidity.They also had that elusive quality called elegance.

The trio of reds served with roasted Quebec duck magret was not quite up to the high standard of the whites. The Henry of Pelham Baco Noir 2004, Niagara Peninsula was a good effort but seemed hollow-centered. The spicy Lakeview Cellars Cabernet Sauvignon 2001 could have been a Bordeaux “petit chateau.” My favorite was the bright and lively Mission Hill “Oculus” 2002, Okanagan Valley, a blend. Each of these reds was honorable, but they lacked that final thrust of ripeness and intensity that we’ve come to expect from the top rung of modern reds.

Say Canada, and most wine buffs will answer “ice wine.” These sweeties, vinified from half-frozen grapes hand harvested by numb-fingered stalwarts in early winter, are big sellers at Asian airport wine shops. Many are made from vidal blanc, a hybrid grape whose high acid counterpoints the intense sweetness of ice wines. But, despite vidal blanc’s vivacity, it too often ends up being one dimensional. The offbeat example that practically jumped out of the glass at dinner’s end, however, was red rather than white: Lakeview Cellars’ Cabernet Franc Ice Wine 2002, Niagara Peninsula – a high-energy distillation of black currant spice crossed with fennel. For me, it was an exciting new species of wine.

PINOT GRIGIO BY ANOTHER NAME Come summer, the usual chilled white wine suspects are trotted out: chardonnay, sauvignon blanc, riesling, maybe the occasional bottle of viognier.And oh yes,there’s that undiminished craze for Italian pinot grigio.But how about pinot grigio’s cousin from Alsace, now increasingly planted in the New World, pinot gris? A white wine relative of pinot noir, pinot gris is unjustly relegated to the second tier of the noble grape varieties, yet it makes a full, round, fruity wine which typically smells like a ripe peach lightly smoked over a woodfire. Late harvest versions (vendage tardive) swing the flavors toward very ripe apricot or nectarine.

Tasting a dozen Alsace pinot gris last month (priced between $12 and $60), I found a frequent flaw: low acidity, which made even flavorful examples seem flabby and lacking in energy – the opposite of Canadian whites. Bolstered by a decent underpinning of acidity, however, the natural heft and yummy flavors of pinot gris make for memorability amidst a galaxy of pleasant wines that induce forgetfulness.

These were my favorite three:

Albert Boxler Tokay Pinot Gris Grand Cru “Brand” 2001 ($35) It boasts shimmering gold color,rich apricot flavors animated by galloping acidity, and a resounding finish. Use of Tokay, a traditional Alsace name for pinot gris, is now discouraged in order to avoid confusion with Hungarian Tokaji.

Zind Humbrecht Pinot Gris 2004 ($21) Deep, delicious, and earthy, with that essential acidity perfectly balanced by its fruit.

Pierre Sparr Pinot Gris 2003 ($10) Big, propulsive scent, and more meaty than fruity in the mouth. Quite dry, with the weight to stand up to the smokiness of summer grills.

SUMMER SCHOOL Wine courses are hard to find when hot weather comes. But at any season, Elisa Cooper’s inventive “Summer Latin Series” would be worthwhile. The Kentucky-born Ms. Cooper, a founding partner of Discovery Wines on Avenue A and now an independent wine consultant, has sought out offbeat and well-priced wines for her course, held on Monday nights at Havana Times Square. Next Monday’s subject, “Not Just Corks and Port,” focuses on the hopping Portuguese wine scene. Chile will be explored on July 17, Argentina on July 24. The final class, on August 7, surveys “U.S. winemakers specializing in Spanish varietals.” Tapas are matched to the wines. $60 a class or $150 for three classes. For more information, call Lara Richardson at 212-398-7447 or email lrichardson@havanacentral.com.