D.C. lawyers have been slow to respond to urgent pleas for contributions to offset more than $700,000 in federal funds cut from legal services programs by the Reagan administration.

About three months ago, a special fundraising committee of lawyers sent an appeal for funds to some 300 local law firms. Only 26 firms and 10 individuals have responded so far, according to the committee's report last week to the D.C. Judicial Conference. The total dollar contributions were $146,500.

Even worse, according to one committee member, "It looks like the same firms and the same people are simply digging deeper into their pockets."

So, for example, you have the big firms, traditional givers such as Arnold & Porter, which kicked in $50,000 in response to the letter. Then there is Steptoe & Johnson, which gave $40,000 and has begun a four-lawyer pro bono program, and Crowell & Moring, which came up with some $20,000 and Arent, Fox, Kintner, Plotkin & Kahn, with $15,000. AL KAMEN &LAURA A. KIERNAN LAWYERS

Several firms have chipped in an extra grand or two and others have offered to increase their efforts, or to take on pro bono cases for the first time.

But it seems only one smaller-sized firm has gotten the message that there is a very serious problem out there.

That firm is Haynes & Miller, a 16-lawyer tax law firm, which contributed $10,000 to the Neighborhood Legal Services Program. "We got the letter and simply felt that we had an obligation to help provide legal services," partner Walter D. Haynes said in an interview last week.

If a few more firms responded with anything even approaching Haynes & Miller's largesse, programs such as the Legal Aid Society might not be in such severe financial trouble, the Neighborhood Legal Services Program might be able to reopen two of its six offices closed by the budget cuts and those who now need legal services more than ever might have a better shot at getting them.

If not, then the D.C. legal community's response to the federal budget cuts will belie the administration's assertions that the private bar would take up the slack when the federal dollars were yanked.