Wordnet 3.0
ADVERB (1)
1. 
 (obsolete) in a mellow manner; 
[syn: mellowly, mellow]
The Collaborative International Dictionary of English v.0.48:
Mellowly \Mel"low*ly\, adv.
   In a mellow manner.
   [1913 Webster]
WordNet (r) 3.0 (2006):
mellowly
    adv 1: (obsolete) in a mellow manner [syn: mellowly, mellow]