Thanks, lbjorker. Two years after I left that comment I still feel the same about that scene and the unknown actress at 59:30. The guy in the scene was the 'college professor,' and I don't know if that generally happened IRL in the 1970's (teachers fucking multiple students), but as a college student in Wisconsin in the 1990's, coeds that looked like her were down to sit on a (condomless) dick after bar time or a fraternity party, and I wasn't even in a fraternity.
Don't turn this off too early. The final fuck and cumshot at 59:30 is what sex is all about. Very pretty chubby chick reverse cowgirls dude. Dude barely manages to pull out before spunking on her leg and bush. Seeing this shot from '74 takes me back to the '90's when I got off the same way with a blessedly large number of curvy, chicks in college. Same big bushes despite the passage of 20 years!