...........Information - Bill oliver ..................
 
On the back of each card is a contest with a letter.  

To win the contest, the collector had to submit 27 cards that 
spelled NU JELL THE PERFECT JELLY POWDER.  Like most contests of
this type during this time frame, one letter was short-printed.  
For this set, it was the letter "H". 

The interesting part is that some animals have 
two different letters on the backs.