Jack Eckerd Corp. yesterday said it was not for sale and, as a result, did not welcome the takeover bid by Dart Group Corp., the Landover holding company run by the Herbert H. Haft family.

On Wednesday, Dart notified the Securities and Exchange Commission that Dart, having just acquired 5 percent of Eckerd's stock for $46.5 million, was considering buying the entire Florida-based company, the nation's second-largest drugstore chain.

"The secret accumulation of stock by representatives of the Dart Group Corp . . . is unwelcome," Eckerd said in a brief statement issued yesterday. Eckerd "has not been and is not now for sale," the statement added.

Dart officials declined to talk further about their SEC filing, which noted that Dart's board met June 1 to discuss buying Eckerd. Dart said it purchased its 1.8 million shares of Eckerd stock in late May, shortly after the price dropped substantially because of Eckerd's announcement that it expected its third-quarter earnings to drop by half over last year's level.

Sources close to Dart said yesterday that for the moment, Dart's purchase was viewed primarily as a good investment and that Dart has no immediate plans to take over Eckerd -- even though it discussed such a possibility at the June 1 board meeting.

Financial analysts and drugstore industry officials, however, predicted that Dart's move may force Eckerd into a sale. Eckerd's stock was the most actively traded on the New York Stock Exchange yesterday, climbing $4 to close at $30.25 a share, with 1.8 million shares traded.

Noting that Dart has a huge sum of cash in its coffers as a result of its $160 million sale last year of its 73-store Dart Drug Store chain, industry officials said that Dart had the money to buy Eckerd.

With no antitakeover measures in effect, Eckerd may be forced to find another firm to buy the chain, financial analysts speculated. "It won't have any trouble finding a buyer," said Elizabeth Parks, editor of Drug Store News.

"It is an extremely successful chain in the drugstore industry and well-established in a number of locations. It is also in an extremely attractive growth industry. People are growing older and need more prescriptions and health-care supplies."

That realization, in part, has prompted a rash of recent acquisitions of drugstore chains, Parks noted. Among them was K mart Corp.'s $500 million acquisition of Pay Less Drug Stores in the Northwest.