It was the B-side of "Fanny, be tender with my love", released as the 3rd top 10 single out of that great album. I recall playing it many times at the school cafeteria jukebox.
Unfortunately, it was buried along big hits like "Jive Talkin" and "Nights on Broadway".
There were so many great songs on Main Course, including "Come on Over" which was recorded by Olivia Newton-John, "Wind of Change", and "At the edge of the universe".
Years later, "Country Lanes" is still one of my favorite Bee Gees' songs.