Lois Spenkelink yesterday joined a crowd of 300 demonstrators at the Florida capitol and the Governor's Mansion protesting the scheduled executions of her son and another death row prisoner.

Attorneys for the two condemned murderers, John A. Spenkelink and Willie Jasper Darden, who are scheduled to die early Wednesday, have filed last-ditch appels with the Florida Supreme Court for stays of execution.

The court agreed to hear oral arguments on the pleas tomorrow. Organizations devoted to abolishing the death penalty, including the American Civil Liberties Union and the Florida Clearinghouse for Criminal Justice, are searching for any possible new argument.

Eight demonstrators in Tallahassee, mostly prison ministers from all over the country, chained themselves to the iron rail fence around the governor's mansion Saturday until Gov. Robert D. Graham came out and spoke briefly with them.

Graham refused to discuss his reasons for signing the warrants but he told demonstrators that unless he got new information he would not change his mind. One of the ministers told Graham, "I can't shake your hand, governor. It's got blood all over it." One of the ministers carried a sign which said "Jesus Died for John and Willie." The demonstrators then removed the chains but maintained an all-night vigil without problems from the security guards.

Spenkelink, 67, visited her son on Death Row at the Florida State Prison at Raiford Saturday and emerged smiling. She said, "I feel better, definitely. John rubs off-his kindness, his strength."

She tried to send word to Graham at the mansion to come out and speak with her. But he never came. Then she asked if Mrs. Graham would come out. A security guard speaking over the "squawk box" from inside the mansion said, "We'll see what we can do." But no further word came except an offer to send one of the governor's staff. Spenkelink declined.

Earlier, on the capitol steps downtown, she told a crowd of demonstrators, "I hope that before the time comes Gov. Graham can have a word with God and that God can change his mind."