The complex, many-line spectrum of FeH, lying in the infrared region between 5500 and 7500 cm-1, has been shown to consist of two separate electronic transitions: E (4)Pi-X (4)Delta and E (4)Pi-A (4)Pi. High resolution Fourier transform spectra from thermal emission have been rotationally analyzed in detail. Lambda doubling in both the E (4)Pi and A (4)Pi states is considerable. The experimentally determined energies and bond lengths of the newly characterized states are in good agreement with theoretical predictions. (C) 2004 American Institute of Physics.