3rd Battalion — 31st Infantry
Lieutenant Colonel Brady…………………. Commanding Officer
Captain O’Donovan…………….. Executive Officer
Captain Brennan. ……………. Surgeon
Captain Stroud…………… Commanding Officer Company “I”
Captain Talbot………… Commanding Officer Company “K”
iLT Thompson………………… Commanding Officer Company “L”
Captain Bell. ……. Commanding Officer Company “M”
The 3rd Battalion, 31st Infantry Regiment, moved into position north and west of Colis on January 4th as reserve force of the 71st Division (Philippine Army), and started constructing field fortifications. Individual holes were dug and barbed-wire wire was strung in front of platoon positions.
The 1st platoon, Company “L” was in the field north of the Colis-Colis — Ventros Road. and about 200 yards west of the National Road. Company Headquarters was in a ravine northwest of the 1st Platoon and the 2nd Platoon was on a ridge about 200 yards north. Company “I” was about 300 yards west of 2nd Platoon, Company “L” and extended west along the high ground. Battalion Headquarters was on the south side of the Colis Road at the junction of the trail leading south and about 400 yards west of Colis. The Battalion Aid Station was on the reverse slope 200 yards south of Battalion Headquarters. Company “K” was in support 300 yards southwest of Battalion Headquarters. The 23rd Field Artillery was located south of the road between Battalion Headquarters and Colis.
The battalion had been in position about 1000 yards north of this area for two days between December 26th and 30th, and had recomnoitered to Layac Junction.
Work on the positions continued until midnight of the 5th. Lieutenant Thompson and Staff Sergeant Flynn, Company “L”, made a reconnaisance of the 3rd Battalion, 72nd Infantry, (Philippine Army) and Company “B”, 31st Infantry on the Sth. The 3rd Battalion, 72nd infantry Command Post was west of the National Read 300 yards north of Colis. Company “kK”, 72nd, was in support and Companies “I” and “L”, 72nd, in the line. The main line of resistance extended from the National Road to a creek about 800 yards west. Company “I”, 72nd, on the right was on the forward slope of the first ridge south of the Layac bridge and Company “L”, 72nd, was dug in in a drainage ditch north of a cane field. They had a very good position. The men dug holes extending 4 feet in front of the ditch which gave them protection from artillery fire. The field in their front was about 400 yards wide and had just been plowed. About 150 yards in front of the junction, Companies “I” and “L” were in a large mango grove. The 1st Battalion, 31st Infantry (US) was on the left of the 3rd Battalion, 72nd Infantry (PA). Their line extended south along the creek, facing west. Company “B” was the company on the right.