A fuzzy fellow without feet

A fuzzy fellow without feet
Yet doth exceeding run!
Of velvet is his countenance
And his complexion dun.

Sometimes he dwelleth in the grass,
Sometimes upon a bough
From which he doth descend in plush
Upon the passer-by.

All this in summer—
But when winds alarm the forest folk,
He taketh damask residence
And struts in sewing silk.

Then, finer than a lady,
Emerges in the spring,
A feather on each shoulder—
You'd scarce accredit him.

By men yelept a caterpillar—
By me—but who am I
To tell the pretty secret
Of the Butterfly!