Newbie question about submodules and git clone.

I have a small personal project that I want to use submodules for.   
For each of the
submodules, I set up a git repository and then used git submodule add
to add them to the super project.  When I try to clone the super
project I get this error

/git_repositories/biatch/.git/refs/remotes/origin: No such file or
directory
Warning: Remote HEAD refers to nonexistent ref, unable to checkout.

What does this mean? Everything is on my laptop so I don't know if
it is trying to go to a URL or something. I'm a newbie and documentation
about this is sparse. Thanks.