Pamelia's latest dahlia photos are the (pollen-coated) bee's knees, a term whose origin is generally attributed to either a 1920s American cartoonist with a knack for coining other nonsensical superlatives (such as the cat's pajamas) or to the shortening in Britain of Shakespeare's "the be-all and the end-all" line from Macbeth (a reference to the coming assassination of King Duncan) to the "Bs and Es," which eventually ended up as "the bee's knees."

Bees' knees—or legs, anyway—are pretty cool. The legs have six sections (as do other insects' legs), and there are pollen baskets on the tibia section that bees fill up when visiting flowers. The joint between the tibia and femur could qualify as a bee's knee, though I don't know if it's the bee-all and end-all. 
(photos by The Naturalist's Notebook's Pamelia Markwood)