A greyhound should be heeded lyke a snake, And neckyd lyke a drake, Backed lyke a bream, Footed lyke a catte, Taylled lyke a ratte.

-Berners, DameJuliana or Juliana Barnes   fl.14c
  Treatyse perteynynge to Hawkynge, Huntynge, Fyshynge, and Coote Armiris.

Frankly speaking, it is difficult to trust the Chinese.Once bitten bya snake, you feel suspicious even when you see a piece of rope.

-Dalai Lama originally Tenzin Gyatso
  Quoted in the Observer Colour Magazine, 5  Apr.

Are not your kisses then as filthy, and more, As a worm sucking an envenomed sore? Doth not thy fearful hand in felling quake, As one which gathering flowers, still fears a snake? Is not your last act harsh, and violent, As when a plough a stony ground doth rent?

-Donne,John
c.1595  Elegies, no.8,'The Comparison'.

A perfumed parlor snake.

-Dunne, Philip
  Daniel Gregg's descriptionof Miles Fairley in TheGhost and Mrs Muir.

The hearings are just like a snake about to devour people.

-Nixon, Pat
  On Watergate. Letter to a friend, quoted in  Julie Nixon Eisenhower Pat Nixon (1986).

The world's great age begins anew, The golden years return, The earth doth like a snake renew Her winter weeds outworn; Heaven smiles, and faiths and empires gleam, Like wrecks of a dissolving dream.

-Shelley, Percy Bysshe
  'Hellas', l.1060^5.

Latet anguis in herba. A snake lurks in the grass.

-Virgil full name Publius Vergilius Maro
Eclogues, 3.93.

   An open place it was, and overlooked, From high, the sullen water far beneath, On which a dull red image of the moon Lay bedded, changing oftentimes its form Like an uneasy snake.

-Wordsworth,William
^1805  The Prelude, bk.6, l.703^7 (published1850).