[R] From a list to a double-list/matrix

[Alaios]

Dear all ,
I would like to extend a list structure to a structure that can hold much more date. 
Please find a small example of my code and my questions regarding it:

lst <- list()

for (k in c(1:mmax)){ # 1 ..max as the f.fxy gets as input order-1.
  for (l in c(1:nmax)){
	sr[findCoord(c(i,j),sr)[1],findCoord(c(i,j),sr)[2]]<-fxy(c(i,j))
      }
    }
    lst[[listcounter]] <-sr # Store the value inside lst
    listcounter<-listcounter+1
  }
}


In the code above I was calculating the values of a matrix sr(200*200 matrix) and then I was storing the whole .matrix inside the list called lst (lst[[listcounter]]<-sr).

This was used for one scenario. I would like to run the same but for 100 different scenarios (randomly created). Thus I want to extend lst to a double-list or a matrix that for every different out of the 100 scenarios stores everything.
The ideal would be to have
lst[[listcounter]][[scenario_index]]<-sr
where scenario_index is the index for the current scenario (ranges from 1 to 100).

Could you please explain me how I can do that in R?

Regards
Alex