In a story yesterday on the assembly races in Prince George's County, the name of a Republican candidate for the House in the 25th District, Joseph A. Finlayson Jr., was misspelled. The age of Timothy S. Williams, a candidate for the Senate in the 23rd District, is 25. The occupation of Horace Hillsman, of Suitland, who is running for the Senate from the 25th District, is community economic development consultant. The new 22nd District in New Carrollton includes sections of Hyattsville, not College Park, as stated. In a story yesterday on the assembly races in Prince George's County, the name of a Republican candidate for the House in the 25th District, Joseph A. Finlayson Jr., was misspelled. The age of Timothy S. Williams, a candidate for the Senate in the 23rd District, is 25. The occupation of Horace Hillsman, of Suitland, who is running for the Senate from the 25th District, is community economic development consultant. The new 22nd District in New Carrollton includes sections of Hyattsville, not College Park, as stated.

Here is how the General Assembly races are shaping up in the Prince George's County districts:

District 13: Two-term Laurel Del. Kay Bienen, Howard County councilman Tom Yeager and Columbia activist Pamela Mack, all Democrats, grapple over the newly drawn state Senate seat shared by Prince George's and Howard Counties. Though Howard has the population advantage in the new district, Bienen hopes to compensate with the allegiance of her home district of Laurel and her familiarity with Annapolis issues. Yeager hopes to benefit from the support of County Executive J. Hugh Nichols and state Senate President James Clark, who bitterly fought the reorganization plan that resulted in the district. Mack is supported by fellow members of the Columbia Association board.

What characterizes this new district is its diversity. It contains activist Columbia, a planned community that is home to a number of Washington professionals, the older, politically moderate community of Laurel, and a number of farm areas in Howard.

For the delegate race, residents will be divided into two subdistricts, with one and two delegates each. There are a total of 15 candidates, including nine Democrats, five Republicans and one independent.

In the new 21st: One of the districts most affected by last year's legislative reapportionment, the new 21st is suffering the consequences with an array of former allies battling each other for a seat in Annapolis. Some of the county's older communities--Hyattsville, University Park and College Park--were divided among their northern, southern and eastern neighbors, with eight precincts going to the old northern 21st district, seven to the old 23rd, and the rest to the old 25th.

A few incumbents from the area are out of the fray (with Del. Kay Bienen running for Senate, Sen. Jack Garrity ensconsed in a judgeship, and Anthony Cicoria running for council), but three incumbent delegates want to retain their seats -- though none of them will run together.

Complicating matters are the total of 13 Democrats who want those three delegate seats, making it the third most crowded race in the state. The candidates include members of two slates, each headed by a Senate candidate, with each composed of different members of the old Democratic organization.

"The district has been dramatically altered and therefore anybody with the slightest ambition and two brain cells to rub together can draw a scenario by which he or she can win," sniffed Del. Tom Mooney, who is handing out packages of forget-me-not seeds to registered Democrats on his door-knocking trail. "Their better judgment is being clouded by blind ambition."

Incumbent Sen. Arthur Dorman faces former state delegate Andrew O. (Sonny) Mothershead, owner of Sonny's Building Supplies, and a cigar-smoking, Cadillac driving cable TV investor who served as Rep. Steny Hoyer's finance chairman. Dorman teamed up with incumbent Del. Pauline Menes, along with newcomer John D'Eustacio, a high school math teacher and member of the Human Relations Commission. All are liberal Democrats.

Dorman and Menes wanted the other incumbent, a rather conservative Del. Tim Maloney, to run with them, along with D'Eustacio, a math teacher and member of the Central Committee. But Maloney, the top primary vote-getter in 1978 at the tender age of 22, got cold feet at the thought of playing ticket-maker after four years of opposition to the politics of the old organization. When Dorman pressed D'Eustacio's case, Maloney called it quits on the ticket.

Mooney, from the old 22nd, is running by himself. He and Maloney, who both bucked the House leadership last session by lobbying (unsuccessfully) to defeat the increase in the drinking age, have been knocking doors individually since May.

Mothershead, a Democratic organization candidate who was defeated in 1978, heads a ticket of two former Democratic central committee members and one newcomer to elective office. This ticket, like many others, is a mixture of ideologies married for the sake of convenient campaigning: Mothershead is conservative, probusiness, and antiabortion. Karen Kuker-Kihl, a teacher union representative and a lobbyist for the National Education Association, is proabortion and prolabor. John Giannetti, an award-winning Laurel sculptor, whose family is well known for their work on the Capitol dome, considers himself moderate to conservative. Barbara Frush is a Calverton civic activist, and is prochoice on abortion but considers herself moderate to conservative on other issues.

Others in the race: Bernie Horn, an Annapolis lawyer and a member of Americans for Democratic Action and a new political group called the New Democratic Alliance, which purports to connect all the people who consider themselves antimachine politics; Claire Bigelow, head of the county's American Civil Liberties Union, who ran a close race against Sen. Jack Garrity in 1978; Regina McNeill, a former campaign worker for Del. Kay Bienen; attorney Joseph Meadow; and Patrica S. Bryant, both of College Park.

In the new 22nd: This New Carrollton district is being stretched to include sections of College Park that had been in the old 22nd. It offered up one of the many filing day surprises: Del. Robert Redding, chairman of the House delegation, filed within minutes of the deadline to run against incumbent Sen. Thomas F. O' Reilly. "I don't know, I guess he wants to go down in a blaze of glory," said O'Reilly. O'Reilly considers himself a sure bet for reelection, in the words of Sen. Thomas V. Miller, "because he's got a sizable war chest, he's the best-looking senator in the delegation, and he's an excellent campaigner. They vote for him in droves."

O'Reilly says he is running with a slate of three, but refuses to say who will be included. Incumbent delegates are Richard Palumbo, Frank Pesci and David Bird, coauthor of the property tax limiting TRIM amendment. Bird appears to be on his own. Favored to run with O'Reilly are newcomer Marion Hoffman of Bladensburg, and Joseph Harris of Landover HIlls, whom O'Reilly encouraged to file on the last day. Other candidates are Robert Colgan of Riverdale and Patrick Tucker of Bladensburg.

In the 23rd: With the death of Sen. Edward Conroy, most Bowie pols thought this election would pass with all the major political factions united in the statewide races. They were wrong.

Ed Conroy's old adversary, Leo Green, a former mayor of Bowie whom Conroy beat by only a few hundred votes in 1978, will be running with Conroy's old slate mates, Gerard Devlin and Charles Ryan. They will be joined by Del. Joan Pitkin, who ran as an independent in 1978 and won.

Challenging them, however, will be Mary Conroy, appointed by Gov. Hughes to fill her late husband's seat until the end of the term. She filed for delegate at the deadline, and may join forces with former assistant sheriff James Hubbard, who quit a $28,000-a-year job a few months ago to campaign full time. Timothy S. Williams, a 23-year-old activist and veteran of two major citizens' referendum drives, filed at the last minute to oppose Green.

Sharon Metcalfe, a Bowie conservative running for a delegate seat, is one of the few Republicans running for a state level race this year. Her campaign spokesman said she would be running on "profamily issues," antiabortion, incentives for small business, solitary confinement for prisoners who engage in homesexual relations, and a crackdown on drugs in prison, among others.

In the 24th: All incumbents in this predominantly black district are running together. Sen. Tommie Broadwater, still the only black senator from the Prince George's delegation, heads a ticket of Del. Nathaniel Exum, Francis Santangelo and Sylvania Woods Jr. Opposing Broadwater is Robert L. Williams of Landover. Running for delegate are Ernie B. Gray of Palmer Park, Lillian Lewis of Landover, and Fred Prince Jr. of Cheverly.

In the 25th: The new 25th District is a blend of the old and the new Prince George's. One of the few truly integrated communities in the county, it stretches from the new single-family homes and town houses of Kettering, wraps around a few scarce farms, reaches out to the older homes of Morningside and barely grazes the District line. Ten years ago, liberal Congressman Steny Hoyer represented the area in the state Senate. Now, with a 60 percent black population, it is represented by a state senator who was one of the only members of the delegation to vote against the D.C. voting rights act.

State Sen. Bernard W. (Mike) Donovan is the only state senator facing a number of opponents this year. The Democrats include James Easter of Largo, a former aide to councilwoman Sue Mills; Alexander Reid, a Suitland Senior High School teacher; Horace Hillsman, a Suitland computer programmer; and Alvin Thornton, also of Suitland. Republican James Whitehead, an aide to Rep. Jack Kemp, dropped out of a congressional challenge earlier this year to run against Donovan.

Ten Democratic candidates are running for the House, including a handful of highly organized black candidates who are newcomers to electoral politics. Incumbent Dels. Lorraine Sheehan and Francis White are dropped from the district-wide ticket, Sheehan after a dispute within the party. White was dropped in 1978 after alleged improprieties with campaign funds, but won independently. There is one Republican candidate, Joseph Finlayor of Upper Marlboro.

District 26: This southern area district, including Oxon Hill, Glass Manor and Camp Springs, will see one of the more intense Seante races this fall. Incumbent Sen. Frank Komenda, who was appointed to fill the seat of former senator Peter Bozick, will face the flamboyant and popular Del. Charles Blumenthal, who is described by his legislative colleagues in words that are usually unprintable. "We have to defeat Blumenthal ," said Sen. Thomas Miller, "The image of the county depends upon it."

Some collegues criticize Blumenthal for voting for pay raises for state employes and then voting against tax measures and other spending mechanisms to pay for them. Blumenthal replies that he is dedicated to his constituents, and, unlike his colleagues, free of allegiances to pressure groups and political kingpins. Blumenthal, who opened his campaign at a gas station to symbolize his opposition to the gasoline tax passed last session, heads a slate of three delegates, all newcomers.

Komenda, described by his colleagues as a workhorse, heads a slate of the incumbent delegates, plus a Democratic Central Committee member. Another Democrat and one Republican are challenging Komenda. Three Republicans are vying for delegate seats.

District 27: Incumbent Sen. Thomas V. (Mike) Miller, a Clinton lawyer, is the only Prince George's candidate running without any opposition. "Ridiculous, isn't it?," he said wryly. Miller, who raised about $40,000 at a winter fund-raiser for his far southern, largely rural district, plans to expend his energies helping his friend Komenda win reelection. The incumbent delegates on his team have opposition from Democrat Xavier Aragona, a builder, and Sheldon Sachs, a Republican.