Source : Webster's Revised Unabridged Dictionary (1913)

Demurely \De*mure"ly\, adv.
   In a demure manner; soberly; gravely; -- now, commonly, with
   a mere show of gravity or modesty.

         They . . . looked as demurely as they could; for 't was
         a hanging matter to laugh unseasonably.  --Dryden.

Source : WordNet®

demurely
     adv : in a demure manner; "the army girl, tall and demurely
           pretty, threw a quick side-glance at her"