Counters for Naglee’s Brigade of the 2nd Division of the IV Corps of the Army of the Potomac. This brigade was placed at the leading edge of the Union line. Very nearly every one of its regiments were scattered all over from the railroad through the swamp on picket duty. This is why every regiment is shown with an information counter specifying its “day of” battle strength.
Naglee got into some hot water following his report on the brigade’s actions at Fair Oaks. His Corps commander (Keyes) was upset that: a) Naglee didn’t concern his comments with just the events of May / June 31/1; b) he discussed actions of brigades other than his own; c) he took command of units that weren’t his and without clear, prior orders.
This strikes me as typical bureaucratic bull. Naglee was like a whirlwind during the battle, riding from one regiment to another, seeking out the problems and resolving them before they turned into something major. He had to take command of a battery of guns that had lost every one of its officers. He had to order the Fifty-fifth New York (1st Brigade, 1st Division, IV Corps) to plug a hole in the lines on the far left before it was exploited by the Confederates and used to turn the Union flank.