my $dir = '/genomes/Bacteria';
  # use single quotes where possible, e.g., no var or \n
  # it's a tiny bit faster

## get the contents of a directory
my @dir_listing = <$dir/*>;
  ## note: using <$dir/*/> would find all the directories

## removes . and ..
while ($dir_listing[0] =~ /^\.+$/)
{
  shift @{$dir_listing};
}

## removes all directories
my @files_found = map { (-d $_) ? () : $_ } @dir_listing;