Much has been said about the end of "Song of Myself" here. It is true that Whitman is asserting his essential unity with everything, not just nature. From the beginning of the poem he asserts his union with his reader:
I Celebrate myself, and sing myself,
And what I assume you shall assume,
For every atom belonging to me as good belongs to you.
So, at the end of the poem, when he says that
I too am not a bit tamed, I too am untranslatable,
I sound my barbaric yawp over the roofs of the world.
He means that like the "spotted hawk" he also is of the wild, his poem an "untranslatable" cry. But the lines you mention give a slightly different twist on the ending of the poem, and perhaps Whitman's purpose in writing it. Lines 7-8:
I effuse my flesh in eddies, and drift it in lacy jags.
I bequeath myself to the dirt to grow from the grass I love,
Here Whitman describes the dissolution of his...
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