on a summer's day, in sultry weather, five brethern were born together.
two had beards and two had none, and the other had but half of one.

smac

Zipper

Here's the brief version from the link:

The five brothers are, in short, the five sepals of Rosa canina and the other dog roses. Two of the five are completely outside the others and have appendages or beard along both edges; two with plain unappendaged edges are completely overlapped along the edges by other sepals; the fifth has one edge appendaged and outside, its other edge plain and inside, in other words it has only half a beard