Hi John,
Zia formation. 
http://www.sharedweight.net/pipermail/callers/2008-July/001641.html
Cheers, Bill
  On 12/05/2014, at 20:22, John Sweeney
<info(a)contrafusion.co.uk> wrote:
 
 Please could someone remind me what name is used to refer to contra lines
 which cross each other, so that those waiting out at the top don't wait but
 do a square dance with each other to the same calls?  Any links or pointers
 also much appreciated.