You probably think this is Christmas. It's actually the day Lynn Martin presents the awful, hideous, disgusting six-foot-high cerise flamingo statue made out of vacuum hose to her sister, Jone Dusek.

Which is Lynn's way of getting even for a year ago.

When Jone gave Lynn a barroom beer clock whose waterfall fell upward.

Which was Jone's way of getting even for the year before.

When Lynn gave Jone a totally tacky velvet portrait of a nude Burt Reynolds.

And so on through the last decade these sisters have gone, through camel lamps, nauseating souvenir dinner plates and more glow-in-the-dark atrocities than you'd see in a month of Tijuanas. Every Christmas, the two sisters try to outdo last year's horrendous gifts with ones that are even worse.

Now, many relatives pass the same Christmas gift back and forth for years. Others prefer progressive gifts. They'll take, say, a handful of shredded wheat and keep adding to it each year, so that after a few Christmases, the gift has to be delivered in an 18-wheeler.

But Lynn and Jone deal on a more artistic plane -- a plane where only the kitschiest of kitsch qualifies.

Of course, the Annual Sisterly Gifts are merely the climax to a year of anticipation -- and a year of taunting.

When Lynn found the Burt Reynolds portrait, for instance, it happened to be March. She immediately picked up the phone and called Jone.

"I've just found your Christmas present," Lynn announced, "and it's hor-r-r-r-ible." Lynn says that keeping her sister wondering about the gift for nine months was almost as much fun as the actual presentation.

There's an especially interesting twist to the annual Lynn and Jone exchange. By mutual agreement, they never throw the gifts away.

The reason is that Lynn is a member of Congress from the 16th District of Illinois. "If the garbage man knew that his elected representative had some of this stuff, it would lower the tone of the neighborhood forever," she jokes.

Next year? Too soon to say, reports Lynn -- but never too soon for either sister to start planning, plotting or rummaging.

Christmas can't come any too soon to the telephones of Washington. After today, thank heavens, there won't be any more confusion between The Santa Tape and The Sex Tape.

Yes, Virginia, all around the Washington area, kiddies have been dialing 976-2121 for several weeks to hear Mr. Claus give a few news bulletins from the North Pole.

Except that some kiddies don't dial so well. Several have fumbled the fifth and seventh digits in the above number. Who answers? A heavy-breathing lass who makes several direct proposals -- and describes them in unusually direct language.

"I'm just getting in the holiday spirit," she began, on one recent day's tape. "So let's say we make some merry, huh, baby?"

Nothing in the next minute was fit for a child to hear. In fact, the lusty lady was so explicit that she might even have embarrassed a guy who's been around the block as many times as Saint Nick.

You can imagine how delighted some Moms and Dads have been when their kids hang up the phone and ask for an explanation of what "Mrs. Santa Claus" just said. But the heaviest embarrassment ought to take hold at good old C & P Telephone.

Surely somebody down there ought to have foreseen this mess. Surely, next year, somebody ought to assign the taped Santa Claus a phone number that's as far away as possible from The Lady With Only One Thing On Her Mind.

CHILDREN'S HOSPITAL

The mail continues to descend in delicious droves. Here are some of the groups that have contributed to our annual fund-raising campaign on behalf of Children's Hospital:

The employes of the U.S. Capitol Power Plant ($20, and thanks to Paul J. Sproesser).

The students at Blessed Sacrament School in Northwest ($75, voted by the student council, at the suggestion of eighth-grader Lin Zogly).

Little River Veterinary Clinic, Inc., of Fairfax ($25).

Ross Vienna Council No. 2, Junior Order, United American Mechanics of Vienna ($50, and thanks to Glenn O. Montgomery).

Coffee Drinkers Unlimited, a gang of guzzlers from the 12th floor of the Office of Audits, DOD Inspector General ($100).

Harr Bible Class, College Park United Methodist Church ($110).

Mosser Design of Northwest ($150).

The Secret Pals, Inc., of Seat Pleasant (a pleasant $50).

Clarke Aerospace Associates, Inc., of Vienna ($100).

The staff at Coles Ethan Allen in Fairfax ($36).

The tenants at The Le Roi, an apartment house at 1838 Connecticut Ave. NW ($100, and a big thank-you to manager Winey Landis).

The Intermediate TAG Class at Mattaponi Elementary School in Upper Marlboro ($220.35 from a schoolwide collection).

Pollard & Tolley Construction Co. of Alexandria ($25).

My old buddies, who still have the craziest name in captivity, The All-Fouled-Up Military Order of the Cootie of the U.S., Auxiliary No. 5 ($50, and thanks, as always, to treasurer Marjorie L. Johns).

The Altrusa Club of Montgomery County ($175).

Phillips-Kleiner Post 5627 of the Veterans of Foreign Wars ($50).

The Woman's Club of Lyon Village ($25).

The Foreign Buildings Operations Staff at the State Department ($742).

Rozansky & Kay Construction Company of Bethesda ($500 in lieu of Christmas cards).

The Washington Alumnae Chapter of Gamma Phi Beta ($33).

Staffers at Hyatt & Rhoads, a downtown law firm ($305).

The Lazy Daisies Extension Homemakers ($50).

The United Forty Niners of Northwest ($50).

The safety patrols at Flower Valley Elementary School in Rockville ($66.65).

The Winston-Knolls Babysitting Co-op in Springfield ($25).

The Maryland Metropolitan Alumnae Association of Alpha Delta Pi ($25).

The employes of Moyer & Sons Moving & Storage Inc. of Gaithersburg (a supergenerous $2,500 in lieu of a Christmas party).

The Family Monetary Fund of D.C. Superior Court ($55).

The Christian Youth Fellowship of First Christian Church, Falls Church ($166.80 obtained via a 24-hour fast held Nov. 23).

American Turkish Association ($500).

Quantum Communications Inc. of Falls Church ($82).

The National Aviation Club of Arlington (a high-flying $600 -- thanks to executive vice president G. Moore Lindsay).

The Falls Church Women's Club Duplicate Bridge Club ($63).

And The Sweet 16 Group at Leisure World ($50.50).

Great show, one and all! Thanks, and Merry Christmas.

TO CONTRIBUTE TO THE CAMPAIGN:

Make a check or money order payable to Children's Hospital and mail it to Bob Levey, The Washington Post, Washington, D.C., 20071.