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Spectrometry is reported for two Zwicky compact galaxies, I Zw 92 and III Zw 77, which have broad emission lines. They are of types Sy 2 and Sy 1, respectively. III Zw 77 has several notable features, including the prominence of forbidden Fe VII, a preference for forbidden Fe II over Fe II, the presence of Bowen fluorescence lines of O III and (probably) N III, and an atypical Balmer line profile. Its Fe/Ne abundance ratio appears to be approximately solar, in contrast to those of several other Seyferts. Line emission has serious effects on the broad-band color of I Zw 92 and probably other Sy 2's as well. A mass is derived for I Zw 92.

Using the results of an accurate variational calculation, the authors present a graphical display of the wavelengths of the H?, H? and H? lines of hydrogen, for magnetic-field values ranging from 0 to 560 megagauss, which is believed to cover the range of fields found in magnetic white dwarfs. This is the first complete detailed compilation of such results.

The author reviews recent research on the environment in which active nuclei reside, namely the dense stellar populations found in the centers of elliptical galaxies and spiral bulges. He discusses new developments concerning the structure and dynamics of nuclei, recent results on the age and chemical composition of nuclear populations, the possibility that important changes in the initial mass function occur in nuclei, limits which can be placed on recent star formation in old populations, and the detection of "submerged" active nuclei in outwardly normal galaxies. Emphasis is placed on problems for which space astronomy experiments are well suited.