The electronic spectrum of germylidene (H2C=Ge), the simplest unsaturated germylene, has been observed for the first time. Jet-cooled H2CGe and D2CGe were produced by an electric discharge through tetramethylgermane diluted in argon at the exit of a supersonic expansion. High-resolution spectra of (H2CGe)-Ge-74 and (D2CGe)-Ge-74, obtained from (CH3)(4)Ge-74 prepared from isotopically enriched Ge-74 metal, have been rotationally analyzed to yield the following r(0) structures: r(0)(')(CGe)=1.7908(2) Angstrom, r(0)(")(CH)=1.1022(5) Angstrom, theta(0)(')(HCH)=115.05(5)degrees, r(0)(')(CGe)=1.914(4) Angstrom, r(0)(')(CH)=1.082(9) Angstrom, and theta(0)(')(HCH)=139.3(11)degrees. The 367-354 nm (B) over tilde(1)B(2)-(X) over tilde (1)A(1) band system consists of prominent perpendicular bands involving the CGe stretching (nu(3)) and CH2 scissors (nu(2)) vibrations and a weaker series of vibronically induced parallel bands involving the CH2 rocking mode (nu(6)). Vibronic bands involving Delta v=2 changes in nu(6)(b(2)) and nu(4)(b(1)) have also been assigned. The fluorescence decays of single rotational levels of the 0(0)(0) band of (H2CGe)-Ge-74 exhibit molecular quantum beats for about 70% of the levels surveyed. Density of states arguments reveal that most of the beats originate from interactions with high rovibronic levels of the ground state. In one case, hyperfine splittings in the Fourier transform of the beat pattern indicate an accidental coincidence with an excited triplet state level. The less frequent occurrence of quantum beats in germylidene compared to silylidene, where they are almost universal, can be attributed to the smaller density of ground state levels at the zero-point energy of the S-2 state in the former.