Question about bind and dig normal behavior

[Paul E Condon <pecondon@mesanetworks.net>]

I have a small home lan, three Sarge machines and two Ruby iMacs. 
I have recently installed bind9 and made one of the Sarge hosts
a name server for the lan and a forwarder for DNS to the outside
world over my NAT internet connection. I have been using /etc/hosts
to define host names and ip address as follows:

127.0.0.1       localhost
192.168.0.11    big.lan.gnu     big
192.168.0.10    cmn.lan.gnu     cmn
192.168.0.12    gq.lan.gnu      gq
192.168.0.13    pauls.lan.gnu   pauls
192.168.0.14    carols.lan.gnu  carols

pauls and carols are the iMacs.  Now I have set up bind9 with cmn as
the name server. I use dig to test whether I have done things
correctly. When a type 

dig pauls.lan.gnu 

on cmn, big, or gq, I get the right answer, namely 192.168.0.13 .
But if I type

dig pauls

I get no answer, only an authority section from the internet in the
response. I had thought I would get the same answer, but I don't. So
my question is, am I simply mistaken in my expectation, or have I
missed something in setting up my data file?

-- 
Paul E Condon           
pecondon@mesanetworks.net