The residents of Adams House I-41 had more than their share of trouble this weekend.

On Saturday night, a man walked into their suite around 8:30 p.m. and robbed them of $36. Last night, a woman whom the Harvard Police say may be mentally ill was arrested for trespassing after she wandered into Adams I-41.

Neva L. Seidman '78 and Kathy Z. Duffin '78, the two residents of Adams I-41, said yesterday the robber gained entrance to their unlocked room Saturday while they were next door watching the Lampoon's fireworks display. They surprised him in Seidman's bedroom when they returned, they said.

Duffin said the man then stuck his hand in his pocket and said he had a gun which he would use unless they gave him all their money.

Seidman said she ran out of the room after realizing that the man "obviously couldn't have a gun in a pocket like his." He then fled behind her, she said.

The two women said the man also stole Duffin's keys and now has an Adams House entryway key.

Seidman said last night she called the police after a woman wandered into her room and started using the telephone and speaking incoherently.

A Harvard Police officer said yesterday the woman may have escaped from a mental hospital. "We had to arrest her so she could obtain medical help." The woman was taken to Cambridge Hospital.