Missing Number Eleven ?

["Phil Joy" <>]

Cheers to all,
                I recently copied a Birds of Australia species list for a friend
who drew my attention to the fact that there was no RAOU map No 11 included
in the list.  On checking in Simpson & Day I found that their number eleven
is in fact the Common Pheasant and the RAOU number for this species is 950.
After checking through the data base and S&D it became apparent that some
numbers have not been allotted RAOU maps and although they are in the main
numerically consecutive, there are several numbers which have no maps
allocated to them.
Is there a reason for this, or is it just one of those things?

Phil Joy         
P O Box 21
Broome
W A            6725