Related Clues:

• XING sites
• Some Monopoly purchases: Abbr
• Madison and Fifth, e.g.: Abbr
• Training systs
• Many Monopoly props
• Lines to Penn Sta
• Cos. with Xings
• Monopoly quartet: abbr
• Some freight cos
• Amtrak and B&O, e.g
• Flight formation adopted by various sea birds
• Birds as a class
• Fifth and others, briefly
• Relatives of sts. and rds
• Marathon rtes., perhaps