Here's another good catalogue of logopeia I pulled off Michael's blog:

'Mándelstam...[uses] words of various contradictory associations: magnificent and obsolete archaism and words of everyday occurrence hardly naturalized in poetry. His syntax especially is curiously mixed--rhetorical periods tussle with purely colloquial turns of phrase. And the construction of his poems is also such as to accentuate the difficulty, the ruggedness of his form: it is a broken line that changes its direction at every turn of the stanza. His flashes of majestic eloquence sound especially grand in this bizarre and unexpected setting.' --D S Mirsky, History of Russian Literature