I've just about got this one down to memory.
From John Dowland's Third And Last Book of Songs and Airs, 1601
The lowest trees have tops, the ant her gall,
The fly her spleen, the little spark his heat;
And slender hairs cast shadows, though but small,
And bees have stings, although they be not great.
Seas have their source and so do shallow springs,
And love is love, in beggars and in kings.
Where waters smoothest run, deep are the fords;
The dial stirs yet none perceives it move.
The firmest faith is in the fewest words.
The turtles cannot sing and yet they love.
True hearts have eyes and ears, no tongues to speak,
They hear and see and sigh and then they break.
Melody link: https://www.youtube.com/watch?v=6DRo0zQesCA
 Turtles here refers to turtledoves, the birds. The critters with shells were referred to as tortoises in the 16th century.