survfit plot question

Hello, I create a plot from a coxph object called fit.ads4: plot(survfit(fit.ads4)) 
Questions: 1. What is the cross mark in the plot ? 2. How does the cross mark in the 
plot relate to either the "rmean" or the "median" from survfit ?

3.  What is the meaning of the "restricted mean" ?  The "upper limit" noted
in the output is the "end of the observation period" (i.e., it is always
the Stop value in the Censored observation)