That would be the 1505s - my dad wore 'em. Not a pretty sight in the tropics - permanent sweat stains under the arms.
But they were comfortable, if not too heavily starched. Both Army and Navy had similar uniforms at the time. I wore 1505s as an AF ROTC cadet in the early '70s. In fact at field training, we only had 1505s and fatigues. (plus that awful plastic raincoat)