[Proj] args list for initializing projections

[Sue Dettling]

Are the projection parameters listed for each projection
on http://www.remotesensing.org/geotiff/proj_list/transverse_mercator.html
a complete list of the parameters needed to initialize
a projection or is this just a partial list. I am wondering if
you also need datum=* or ellps=* or whether there are default values
if these are not set.

Thanks,
Sue