Patrons of Washington-area massage parlors are letting their fingers do the walking, and leaving the driving to the masseuses and masseurs.

The "house call" is the newest twist in the masage business, and by most accounts, business is booming. The yellow pages list 32 call-out massage services, and the usually fill a column in the Washington Star classified advertising columns.

The patro often just telephones in his pleasure and his price and waits for the knock at the door.

It is not unusual for some call-out services to get 30 calls a day at a minimum of $50 a massage, said the man who answered the phone at the Something Different service on G Street SE.

Police throughout the area said a call-out operation compared to a massage parlor offers more privacy for patrons, more opportunities for tax avoidance, and less opportunity for police surveillance.

But police say at least some of the call-out services are fronts for prostitution.

D.C. vice squad Sgt. William C. Novinski estimated that his unit has investigated about 25 call-out services in the District and that those investigations resulted in "about 22" arrests for prostitution. Of the 22 cases, about 20 ended with convictions, Novinski said.

The District has a ban on "cross-sexual massages" (a massage by a member of the opposite sex) in any massage parlor licensed in the District.

Because the ban applies only to "establishments licensed under this section" of the D.C. code. It does not cover out-of-parlor massages, Novinski said.

A woman answering the phones at one of the area's most prosperous call-out services did not deny that the massage service frequently also involves sex.

"If there wasn't any demand for the service we offer, there wouldn't be any service. What we offer is a massage and what the girl does above the massage is her own business and the customer's business," said.

The woman estimated that about three-quarters of the calls her telephone answering service refers to masseuses result in some sexual favor.

"I don't know why there are still so many girls on the streets," she added.

The problem has become particularly perplexing for Alexandria, where the City Council has recently given preliminary approval to an ordinance tightening the licensing requirements for massage parlors only to find the call-out business has eluded regulation.

"We had a whole group of attorneys and police people and we couldn't find a way to regulate (call-out services)," said City Manager Douglas Harman. He said he was not aware that Fairfax has approved an outright ban on the call-out services.

"It's really uncontrollable. They have a wide open field," said Capt. Walter L. Johnson of Alexandria's vice unit.

Fairfax County Investigator Joseph G. Duncan estimates that as much as 90 per cent of Northern Virginia's call-out business may be based in Alexandria.

There are five call-out massage services in Alexandria, Johnson said. Setting them up is simple.

Alexandria requires only a business license for an answering service and does not inquire into the specific business to be conducted.

"It takes about 20 minutes. It's a very simple form. It takes two or three minutes to fill out. There's no delving into a person's background. It's strictly a revenue license," according to Erin Lee of the city's business license office.

The applicant pays a licensing fee of 35 cents for each $100 of gross receipts expected to be made from the enterprise.

The city's zoning department also does not scrutinize the requested license, if he answering service is to be located in a commercially zoned area.

"There's no basis for turning them down," said Betty Hill of the zoning department. "But we don't want anything like 'masseuse' on the application. If it comes here with 'masseuse' of 'massage' on it, we cross it off," she said.

The zoning administrator requested that "masseuse" or "massage" be crossed out on the license application because he was concerned about the possibility that the call-out operators might claim the city approved the site for a massage parlor rather than office use, Hill said. But by eliminating the words masseuse and massage from the license, no one later can readily determine the nature of the answering service.

One such service in Alexandria is located at 101 N. Alfred St., which has several separate listings in The Star's classifieds. Among them is the Hotline, specializing in "English massages," which the woman answering the phone described as an exercise in "dominance and submission;" the Other Side, offering the male masseurs for men; and the Diplomatic Corps, which deals in escorts for men and women.

"It's like a Hoaward Johnson's ice cream parlor. You call to see what flavors they've got," said Capt. Johnson.

The call-out services say they get a percentage of the massage receipts, usually, 40 to 60 per cent of the flat rate for the massage (about $50). The masseuse or masseur is driven to the caller's house by a man who serves as a "security man" to make sure there is no trouble, Johnson said.

What the masseure or masseur makes in tips or for extra services, he or she keeps, Johnson said.

District police said they are concerned because the house call operations have opened up what they believe is a second front for prostitution and because such crimes as larceny or robbery sometimes occur along with prostitution.

Prince George's County police said they believe the call-out services are doing business in the county but "it's so hard to detect."

Montgomery County vice squad Sgt. F. W. Whalen said the call-out services operating in the District and Virginia are a "major problem" for Montgomery County. The county has a ban on "cross-sex massages" that covers massages both in and out of the parlor.