my @descriptor_array = (
   [ 1, 2, 3, 4 ],
   [ 2, 3, 4, 5 ],
   [ 3, 4, 5, 6 ],
   [ 4, 5, 6, 7 ],
);

my @insomearray = (0, 3);

for my $array_no (@insomearray) {
    my $array = $descriptor_array[$array_no];
    print("$array_no $array @$array\n");
}