Possible Clues:

• "And so forth"
• Substitute for the unlisted
• List-curtailing abbr
• Alternative to an ellipsis
• "I could go on, but won't"
• ''Yadda, yadda, yadda''
• "And so on" letters
• Ink-saving abbr
• Lister's abbr.
• 'You get the picture'