All-conquering Ayr added a sixth Premiership scalp and another five points to the bank with a comfortable victory.
Their undefeated status was safe after the first 40 minutes when they ran in four tries while the home team chased shadows among the pink and black jerseys.
Ayr coach Peter Murchie had asked his side to be more ruthless and they responded.
Murchie’s opposite number Peter Wright warned his players they would be swept away if they didn’t buck their ideas up. It was a case of told you so by the end.
The early signs of a ruthless streak were on show in the way the Ayr backs combined after only a few minutes to short pass their way up the left wing with the ball left in Stafford McDowall’s hands for the try. Stand-off Frazier Climo converted.
It wasn’t quite ruthless enough though, because the reply was instant with Muir winning a five-metre lineout and hooker Johnny Matthews crashing over. The conversion attempt was wide.
Ayr were taken to the other end of the pitch by a massive Climo punt from inside his own half. The Muir defence stopped the maul on the line but opened up soon after to allow McDowall to cruise through for his second try. Climo converted.
A period of sustained pressure by Muir was spoiled when they kicked away possession only to set up Ayr for a flowing attack that ended with full back Grant Anderson diving in to score. Climo converted from the touchline. And the bonus point try came just before half-time when Climo slipped through some slack tackling to reach out and touch down. He missed the conversion.
After the break Muir battled manfully but failed to make much of a dent in the Ayr defence until winger Jordan Edmunds got the ball on his right wing and ghosted past a couple of defenders to score. The conversion was wide.
Ayr emphasised their superiority by spurning an easy three points from a penalty in front of the posts, instead kicking for the corner, rolling the maul, and going wide for Robbie Nairn to cross out wide. The conversion attempt was short.
Ayr went down a gear, as replacements came and went, but a sixth unconverted try followed for skipper Blair Macpherson.
Muir stuck to their task and were rewarded with a late try by skipper Jonathan Matthews, his second, converted by Robin Weersma.