For eight straight hours last week, members of the Prince George's County Council argued, yawned and chain-smoked their way through a marathon 23-page agenda. When they were finished, they had cleared the way for a November vote on an amendment to the county's property tax cap and acted upon 55 other pieces of legislation.

It was the last substantial meeting of the council elected in 1978. Among the bills the members dealt with were measures that restricted the sale of cigarette rolling paper, established a trust fund for the poor, adopted a 10-year water and sewer plan, raised the tax on video games, restricted locations for some types of halfway houses and made it easier for county employes to testify before the council.

"What a flood of paper the council generates," said state Del. Gerard Devlin, who poked his head into the council chambers before disappearing into the Administration Building cafeteria for lunch. He offered a quick reminiscence about the pre-home rule days of government by five county commissioners: "We oversolved the home rule problem. Eleven people waste more money than five."

The council deliberately packed its agenda the past few weeks to avoid the need for another meeting until after the November elections--except for a session Aug. 24 to consider a few bills--because a majority of the members will not return to office. One council member is moving from the area; one decided not to run for any office; one is running for county executive, another for clerk of the court and, because of redistricting last fall, two members are facing each other in the Sept. 7 primary.

The council traditionally recesses during August, and state law requires it to conclude zoning matters by Oct. 31 in an election year. But this council decided to expand that directive to include all legislation.

Ella Ennis, Republican candidate for the 9th district council seat, criticized members of the all-Democratic council for taking a "taxpayer-subsidized vacation" for their campaigns and said they should return part of their salaries. Others charged the council with attempting to ram through major legal changes on the sly.

But council administrator Sam Wynkoop argued that it would be "psychologically difficult" for members to legislate with a lame-duck majority just before or soon after the primary and that it could be unfair to the voters.

As a result, the council members, their faces drawn and working in an atmosphere charged with their occasional bickering, waded through several dozen sparsely attended hearings at the July 27 meeting and voted on bills, passing most of them unanimously. Among the measures were:

* A bill, approved 10 to 1, allowing voters to decide whether they want to amend TRIM, the property tax revenue cap. Sue Mills, who voted against the measure, argued it would mean automatic tax increases. Council Chairman Gerard McDonough, who sponsored the bill, asked Mills if she wanted to "hold a bake sale" as a new revenue source

* A measure restricting the sale of cigarette rolling papers to discourage marijuana smoking. Mills, who introduced the bill, said it closed a loophole in the county's ban on the sale of drug paraphernalia. Council members Deborah Marshall, Floyd Wilson and Ann Lombardi called the bill ridiculous and unenforceable.

"Shouldn't we outlaw dollar bills?" Marshall asked as Mills glared, "because people use dollar bills to snort cocaine,[and]spoons, safety pins, stirrers at McDonald's, garter belts. Do we have to ban everything that everybody uses to[take]drugs?"

The bill originally limited sale of papers to stores where loose tobacco is sold. It was amended, at a paper manufacturer's suggestion, to say that papers could be sold with "over-the-counter tobacco products," including cigarettes, and passed 7 to 4.

* A measure establishing a $400,000 trust fund for the poor, to be administered by several charitable groups, from the proceeds of the sale of surplus land. It passed 8 to 3. Opponents said the fund would duplicate county services.

* A bill requiring county employes to testify before the council when requested and providing assurances that they may appear without "threats, restraints or retaliatory actions." The bill was prompted by accusations by some employes that a former Department of Aging director refused to allow workers leave time to attend hearings. It passed 11 to 0.

* An act increasing the number of town houses permitted in a "recreational community development," from 50 percent to 65 percent, passed unanimously.

* A bill describing the order in which referendum questions will appear on the November ballot. There are 11 questions, including requests to approve bonds for a new jail, a police station, roads and an Upper Marlboro mall. The question asking voters whether they approve of a modification of the TRIM amendment, which limits property tax revenue to the 1979 level of about $143 million, will be listed last on the ballot.

The council decided to hold other bills until the August meeting after citizens or the county executive made clear the legislation would create controversy. The measures included:

* A bill to set standards for clinics that say they offer medical care.

* Zoning bills to modify some provisions for approval of comprehensive design zones.

* A bill to modify some laws designed to protect trees from destruction during land development.

At the end of the day, council members gathered for beer in a private meeting room. "It's a mixture of sadness and relief," said Parris Glendening, who served as a council member for eight years and is running for county executive. "This is over, and we can get on with the rest of our lives."

"I'm coming back in the fall," said Mills, who is running for reelection against incumbent David Hartlove. "Four years have passed, that's all."