check if type is valid pg type - Mailing list pgsql-novice

Hi all,

I need to check, whether a type is a valid postgres type or not. My first take was to check in the pg_type table.
However,pg_type does not list types such as integer (but it does list int4) or float (but it does indeed list float8).
Whatis the best way to check whether a type is valid or not? 

Thanks,
Dominik