THE SENATE has managed once again to neglect a familiar weed. In the convenient rush of other business, the members have somehow forgotten to dig up honoraria.

In the old days senators were sometimes kept on hidden "retainers" by the interest groups they faithfully served. Today the system is slicker. The members are paid "speaking fees" of up to $2,000 an occasion. They can keep the equivalent of about a third of their official salary; the rest must go to charity.

No one would propose a legislative users' fee in which part of Congress' salary was paid by the interest groups whose fortunes it controls. Yet that's what we have. The House sensibly struck down this contaminated and demeaning system a year ago, banning honoraria in return for an offsetting pay raise that had the doubly useful effect of freeing up the pay of federal judges and senior officials in the executive branch. To provide both leverage and cover for raising its own pay, Congress had previously held them hostage.

The Senate, however, kept the honoraria system mostly intact for itself. It is easier for senators than for most House members, who are less well-known, to earn the maximum in honoraria -- and there is always an uproar when Congress votes itself a pay raise. The path of least resistance for most senators was to vote for a small pay raise in return for a small reduction in honoraria, and otherwise to maintain the status quo.

This year the issue was renewed by Sen. Chris Dodd, and the Senate did the right thing -- sort of. It voted to ban honoraria, but attached the ban to the campaign finance reform bill. That is now dead, too, for lack of enthusiasm among House Democrats as well as among Republicans, so once again the senators have been able to have it both ways on honoraria -- to vote against them and to keep them.

The Senate could still mend them if it chose; there's time. It had an object lesson in some of the pitfalls of the system of foraging for pay earlier this year in the case of Sen. Dave Durenberger. He was censored for having followed the beaten path too far, but the path itself was preserved. It's hard to remember, but this started out to be a Congress partly about ethics. The Senate should do its speaking for free.