How to find out what service is running on a port

[Sean Kelleher <kellehers103@home.com>]

Hi folks,

I've got errors that are continually popping up to STDERR about a
packet being rejected by my firewall, bound for port 65535. this
behaviour itself is normal -- my firewall should reject this packet --
but i'd like to know what service this packet hopes to reach. i've
checked the relevant files (AFAIK -- /etc/services, /etc/inetd.conf),
but don't see anything that applies.

anyone know where i could look to find out which service this is? 

TIA,
Sean
-- 
"The discovery of vinyl alcohol is significant"