https://www.google.com/webhp?sourceid=chrome-instant&ion=1&espv=2&ie=UTF-8#q=+cocoa+cup+and+lid+with+north+wind+face+on+handle

The squiggle is not a makers mark !! If you notice the numbers are hand painted before firing and the squiggle mark is probably the mark of the person who painted the numbers !! Many mfrs paid the artists who did the design on the cup by piece work !! They were paid according to how many they completed !! Their mark,, whatever it was, was a way of counting the number of cups or saucers painted. !!
Each artist would have a different mark so no confusion as to who did or did not do this work !! They were free to use any mark they wanted as long as it wasn`t duplicated and they wanted something easy and fast to paint !!
The face on the handle ( can not see it well) appears to be the North Wind face used more in Scandinavian and German countries !! See examples of the North Wind Face ( or some call it the Green Man if it has leaves for hair) as used on furniture above !! Was a common decorative item in some cultures !! I think its the symbol for the good things in life,,,money, luck,, fertility ect !!