AT72 CREW LWOC.

Narrative

WE WERE VECTORED FOR A VISUAL APCH TO RWY 26R IN ATL. WE WERE CLRED FOR THE APCH AND TOLD TO CONTACT TWR 5 MI OUT. WE LANDED ON RWY 26R AND TAXIED CLR ON THE FIRST HIGH SPD TXWY. I TOLD THE FO THAT I DID NOT HEAR OUR HOLD SHORT INSTRUCTIONS AND ASKED HIM IF WE WERE TO HOLD SHORT OF RWY 26L AT TXWY B6 OR TXWY B4. HE SAID THAT ATC DID NOT SPECIFY WHICH TXWY; AND THAT HE WAS GOING TO BE TALKING TO COMPANY OPS ON THE #2 RADIO TO CONFIRM OUR PARKING SPOT. I REALIZED THAT THE TFC ON THE #1 RADIO; WHICH WAS USED FOR ATC; WAS APCH CTL TFC INSTEAD OF TWR. AT THIS POINT I REALIZED THAT WE HAD LANDED WITHOUT CLRNC FROM THE CTL TWR. I CONTACTED TWR AND WAS TOLD TO CROSS RWY 26L AND JOIN TXWY E TO THE RAMP. I FAILED TO MONITOR THE FO'S ACTIONS AS THE PNF AND DID NOT NOTICE THAT HE FAILED TO CHANGE TO TWR FREQ AT THE APPROPRIATE TIME. ALTHOUGH I NOTICED THAT HE FAILED TO VERBALIZE THE COMPANY'S CHKLIST AT 500 FT AGL (WHICH SHOULD HAVE INCLUDED CONFIRMATION THAT WE WERE CLRED TO LAND); I DID NOT THINK TO QUESTION HIM ABOUT WHETHER WE HAD CONTACTED TWR OR NOT. AS CAPT; I NEED TO MAINTAIN GREATER VIGILANCE IN MONITORING THE FO'S ACTIONS; REGARDLESS OF WHETHER I AM THE PF OR PNF.