Bigfoot.

That is all the F.B.I. said (well, tweeted) Wednesday when it released 22 pages of eyebrow-raising documents related to a 1970s hair analysis it conducted at the request of a well-known Bigfoot researcher.

The researcher, Peter Byrne, then the director of the Bigfoot Information Center and Exhibition in The Dalles, Ore., had a simple question for Jay Cochran Jr., the assistant director of the F.B.I. laboratory division: Have you been testing possible Bigfoot hair samples? And if not, would you like to start?

The 1970s were something of a heyday for Bigfoot researchers — the grainy Patterson-Gimlin film, which claimed to show one of the creatures strolling through a California streambed, was shot in 1967. Mr. Cochran did not seem terribly surprised by the question.

The F.B.I. had been asked several times in the past year whether it had been testing hair samples for possible Bigfoots, Mr. Cochran replied. “However, we have been unable to locate any references to such examinations in our files,” he wrote.