You might be thinking of bottle conditioned beer.
I don’t know if those are even sold in the US anymore.
They continue fermenting after bottling and require different storage conditions from most beers.
Mr. Mew loved Morland’s Hen’s Tooth, but that was discontinued years ago.
I don’t think he’s had a bottle conditioned beer that he hasn’t made since then.
Many years ago, I was fond of Cooper’s Real Ale. There was yeast in the bottom of each bottle, and you could either pour carefully or just swirl it up. Haven’t seen it in a long time, but I don’t go to bars now, and very seldom drink beer at all.