The Lautrec Sisters are a quartet of dancing rats who audition for The Muppet Show in episode 208, performing "The Garbage Can-Can."
Kermit enjoys the act, leaving a nervous Fozzie to exclaim, "He liked the dancing rats? Oh, what chance does a bear have?"
Two of the rats were puppeteered by Louise Gold and Jerry Nelson.[1]
References
The Sisters' name is a reference to Henri de Toulouse-Lautrec, the 19th-century French painter whose 1893 portrait of can-can dancer Jane Avril has become the quintessential image of the free-spirited French dance-hall girl.