For over 50 years, Tulane and St. Charles were essentially opposite sides of what was effectively a single loop streetcar line.  However, there was one significant difference: Tulane served the loop at the foot of Canal Street, while St. Charles did not.  (See Group 10.)  So one is not surprised to see the St. Charles transfer marked “Not good on Tulane.”  What is surprising is to find two slightly different Tulane transfers, as seen here.  The first one, marked by a three-sided red line at the top and bearing a cryptic letter “R”, states “Good on Tulane Outbound at Bourbon and Canal Only.  Not good on St. Charles.”  The second, marked by the letter “S”, is inscribed “Not good on St. Charles Except at Baronne and Canal Only.”  All the other restrictions on usage of the Tulane transfers are the same on both R and S.  These two transfers and the St. Charles transfer are dated April 19, 1949.  An older version of the Tulane R transfer, dated October 1, 1937, shows a complete red box around the date number.  It appears to this author that the R transfer made it possible for a through passenger to ride to Canal Street on a Tulane car, then skip the trip to the foot of Canal Street by transferring to an outbound Tulane car at Carondelet/Bourbon Street.  The S transfer would have made it possible for a would-be St. Charles passenger to catch an outbound Tulane car on Canal between the loop and Baronne St., then transfer to an outbound St. Charles car just before it turned up Baronne.  Note the absence of the usual “Not good on issuing line” notation on the reverse of the first coupon of the R transfer.