H. R. (Peck) Humphreys Jr. is a very wealthy and very loyal Democrat who did more than his share to help elect Charles S. Robb governor of Virginia last year. A millionaire fishmeal tycoon from the Northern Neck, Humphreys served as vice chairman of Robb's finance committee. He also kicked in $11,000 of his and his firm's money to Robb's campaign coffers.

So after the Democratic Party's smashing November victory, Humphreys says it was only natural that he would ask his new governor for a suitably "major" post in state government.

"When you work hard for a candidate, I don't know why you couldn't expect some kind of an appointment," say Humphreys, whose Kilmarnock menhaden fish firm is the largest of its kind on the Atlantic coast. "That's certainly been true when the Republicans were in office."

Humphreys was finally rewarded for his partisan labors the other day. He was named to the powerful State Highway and Transportation Commission, one of 1,142 appointments announced by Robb as part of a wholesale transformation of the state's boards and commissions.

There are 194 of these boards, ranging in power and prominence from the highway commission and the Air Pollution Control Board to such relatively obscure panels as the Virginia Egg Commission, the Virginia Sweet Potato Commission and the Advisory Committee on Furnishing and Interpreting the Executive Mansion. Appointment to these august bodies has long since become a quadrennial Richmond ritual--a time-honored exercise in political patronage in which the new governor rewards his most loyal campaign workers and contributors with appropriate sinecures.

This year Robb had vowed the process would be different. Qualifications for office were to be his central theme, he proclaimed. Opening up state boards to long-excluded blacks and other minorities also would be a factor. Political loyalties would take a back seat.

"If you're looking for a pattern in these appointments," said George Stoddart, Robb's press secretary, "it was the selection of people who would strengthen these boards. Any political considerations were secondary."

More than a few disgruntled Republicans are finding such pronouncements difficult to swallow. As they see it, Robb has played the game just the way it's always been played--only more so.

Consider, Robb's critics say, Joseph M. Guiffre. An Alexandria beer distributor, Guiffre backed Robb to the tune of $3,883 in campaign contributions last year. He was first named to fill a vacancy on the highway commission in February and this month found himself reappointed to a full four-year term.

Then there is W. Wright Harrison, former head of the Virginia National Bank in Norfolk, who contributed $4,000 and who was selected to the Virginia Port Authority. And W. Gibson Harris, the Richmond attorney who gave $10,000 and who wound up on the Advisory Board of Industrial Development, and Myron B. Erkiletian, the Northern Virgina builder who contributed $2,000 and who was named to the Board of Conservation and Economic Development.

The list goes on, right down to Charlene B. Ruden, a Robb campaign volunteer from Reston who was picked for a slot on the Virginia Milk Commission. "Everyone I've seen so far has been a Democrat or a fund-raiser," groused House Minority Leader Vincent F. Callahan, a Fairfax Republican. "It's much more political than his Republican predecessors had done. They're reverting it back to the days when you had to be a dyed-in-the wool, primary-voting Democrat to get an appointment."

That is no doubt an overstatement, since many of Robb's heftiest contributors and appointees--Harrison and Erkiletian, for example--are political independents who swing back and forth between the two parties, thus managing to stay plugged in no matter who is in power.

And it is also true that Robb did follow other criteria in selecting many of his appointees. Laurie Naismith, the former Robb campaign worker who as the new secretary of the Commonwealth handled the appointment screening process for the governor, says an unprecedented effort was made to name blacks and women to virtually every board and commission. "We were trying to give different groups access to appointments," she says.

Although the final tally on minority appointments is not yet in, Robb staffers proudly point out that they have named blacks for the first time to such traditionally all-white bastions as the State Board of Elections, the Alcoholic Beverage Control Commission, the Board of Commerce, the Board of Contractors and the Virginia Employment Commission.

For their part, the Republicans say they don't necessarily object to the governor paying off his campaign debts to top black suporters such as state Sen. Douglas Wilder of Richmond. A solid black vote was a key element in Robb's winning coalition. They do find objectionable, they say, the governor's self-righteous piety.

"What I resent," says Callahan, "is when he says he's appointing these people on the basis of ability and stuff like that."