The format is:
List of 50
\$ 1 :`data.frame': 100 obs. of 6 variables:
..\$ class: int [1:100] -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 ...
..\$ F1 : num [1:100] -0.252 -2.482 -2.497 2.220 0.727 ...
..\$ F2 : num [1:100] 2.73 1.48 -2.13 -1.64 -2.62 ...
..\$ F3 : num [1:100] -0.864 0.411 0.136 -1.809 1.344 ...
..\$ F4 : num [1:100] 1.535 1.335 0.482 1.682 0.834 ...
..\$ f : Factor w/ 50 levels "1","2","3","4",..: 1 1 1 1 1 1 1 1 1 1 ...
... and then 49 similar ones.