What is a camp shirt?

Apparently, both the Shop Manager and I were confused as to what made a shirt specifically a camp shirt.  I thought it was the tabs on the sleeves that held rolled sleeves in place (you know--the ones that come from inside and button to the outside of the sleeve?).  Gloria thought it was pockets that make a camp shirt.  After a little research, it seems we are both mistaken.  What really makes a shirt a camp shirt is the collar.
So far, Wikipedia is the only reference I have found on line:

A Camp shirt is a loose, straight-cut, short-sleeved shirt or blouse with a simple placket front opening and a "camp collar" - a one-piece collar (no collar band) that can be worn open and spread or closed at the neck with a button and loop. It usually has a straight hemmed bottom falling at hip level, not intended to be tucked into trousers, etc. It is often the base for fancier fabrics such as Hawaiian prints, or tropically inspired weaves and patterns.


After reading this, I remembered the camp collar or convertible collar from one of my flat patterning books.  I am apt to believe this is probably the most accurate definition.  If anyone else has a source or ideas, please let us know!