For the third time in less than an hour, Montgomery Taxicab driver Barbara Patton steered her station wagon through the darkened subdivision streets of Germantown. Waiting for her at a cul-de-sac lined with town houses was Brian Ferguson, an electrical engineer who had just spent a restless hour waiting for another cab to come.

Earlier he had called Barwood Cab Inc., the 300-vehicle fleet that dominates the taxi industry in Montgomery County. But a Barwood cab never came, said Ferguson, 33. He tried Patton's seven-vehicle Montgomery Taxicab company next, he said, because the Yellow Pages ad emphasized that it serves Germantown.

Tonight, the Montgomery County Council is scheduled to hear testimony on a proposal to overhaul the county's 30-year-old taxi code and increase the current 384 taxi licenses by about 40 a year.

Some cab owners and drivers who work the growing upper county plan to urge the council to give them a chance to put more taxis on the streets of developing communities such as Germantown.

Independent drivers complain that Barwood's dominance has resulted in a textbook example of what happens when one company monopolizes a business, with overworked drivers on the road 12 hours a day to make their ever-increasing taxi rental payments. In addition, these drivers say, Barwood concentrates its business in the more profitable lower section of the county, where demand is greater.

But other taxi owners, worried that too many drivers are trying to carve a living out of the Montgomery market, are urging a tight limit on licensing.

County Executive Sidney Kramer is proposing that a maximum of 160 regular licenses, as well as additional licenses for taxis equipped with wheelchair lifts, be granted over the next four years by lottery to qualified applicants. That would give Montgomery about 600 taxi licenses by the early 1990s. An association of county taxi drivers is calling for further study of the market and issuance of no more than 40 new licenses over the next few years.

Nearby Prince George's County has about 700 taxis, and drivers say Prince George's cabbies are known to cross the border illegally to take advantage of the market in eastern Montgomery. Across the Potomac River, Fairfax County has 277 taxis -- and grants new licenses based on demonstrated need. The District of Columbia, widely regarded by transportation regulators as a taxi free-for-all zone, has more than 10,000 licensed cabs.

Kramer proposes that starting in the 1990s, Montgomery's additional licenses be indexed to population increases.

County Council member Neal Potter, head of the council committee that deals with transportation, proposes a more dramatic solution: Ending taxi restrictions altogether.

Potter would grant licenses to all qualified applicants, and would allow taxi companies to set their own rates. The county currently limits fares to $1.80 for the first mile and $1.20 for each additional mile. Potter contends that taxis "have the potential to do a lot to solve our transportation problem." As a service industry, Potter said, taxi companies should be allowed "to respond to the marketplace."

Tonight, Bill Middleton, owner of Taxi Taxi, a one-cab firm serving the upper county, intends to tell the council that there is a large demand for more cab companies, and that he thinks competition is good for the county. "When you have only one company dominating certain areas of the county, people have to rely on that one company," he said.

Over the years Barwood has become the dominant company by buying out five other firms and buying up individual licenses for $15,000 to $20,000 or more. It is currently the affiliate company for about 40 individual cab owners and is the county's main contractor for taxi transportation.

Barwood Vice President Lee Barnes, son of the late Barwood cofounder Harrison Barnes, countered suggestions that his company concentrates on the lower section of the county by saying that more than half of Barwood's runs are north of Garrett Park and Wheaton.

Montgomery's transportation director, Robert S. McGarry, thinks the county needs another 150 taxis at most, and that people who move "out to the country" should not expect intensified, urban cab service.

John Eckert, a Barwood-affiliated cab owner who is president of the Montgomery County Taxicab Association, said the upper county is getting more attention from drivers than it used to, but calls it a "kind of a sleeper" for the taxi industry.

None of the proposals under consideration stipulates that more service be extended to any specific part of the county.

McGarry contends as well that Montgomery "has the best taxicab service in the country," with rigorous self-policing by Barwood, which makes its money from cab rentals and dispatch fees from affiliated taxi owners, and by the only other large county cab company, Silver Spring Taxi, operator of 60 cabs. Some of the county's 500 licensed drivers, on the other hand, say that service is so firmly in the grip of Barwood that there is little room for innovation, both in working conditions and income for drivers.

"More people would ride cabs if service were better and they could count on them more," said taxi owner Andy Valakos, who is affiliated with Montgomery Taxicab. In areas such as the Rte. 29 corridor and parts of the upper county, "a lot of people are finding other ways to go because they can't count on cabs," he said.

The last batch of 20 licenses was issued by the county several years ago.

Valakos and other individual owners said they welcome the chance to acquire additional licenses, as long as Barwood isn't allowed to succeed in its bid for half of the new licenses.

He said that while there are "parts of the county where our response time is not what we'd like to see it," the majority of customers are picked up within 20 minutes of calling.

Betty Healy, a cab owner affiliated with Barwood who drives mainly in the upper county, said most of the demand for cabs there comes at rush hour, when all the roads are jammed with traffic. "There would be plenty of cabs if we didn't get tied up in that traffic," she said.

At other times of day, drivers can sit at a cab stand in Germantown for hours without receiving a call, Healy said. "Whatever the county does is a real concern to all of us," she said. "If the county puts too many cabs out there, we won't be able to make a living."