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Visual and infrared photometry of strongly polarized QSOs (BL Lacertae objects) is reported. Spectral flux distributions of these objects are discussed in combination with results from earlier studies. With the exception of the well-resolved galaxies Mkn 421 and Mkn 501 only one object (1218 + 304) has a change in spectral index easily explained by the presence of an underlying galaxy. Six other sources appear to have either a break in their spectra near about 1 micron or a smoother general steepening of their spectra at shorter wavelengths. A spectral break at this wavelength may be attributed to a low flux of nonthermal radiation superimposed on a stellar energy distribution or by nonthermal electron energy losses.

New ultraviolet data are combined with optical data to investigate the wavelength-dependent extinction of the stars W46, W90, and W100 in the young galactic cluster NGC 2264. The observations of W90 confirm the existence of anomalous (circumstellar) dust extinction with a ratio of total to selective extinction, R greater than 7. This extinction is most easily explained by a graphite-silicate mixture with larger mean sizes than are present in the diffuse interstellar medium. For W46 and W100, the grains are likely to be gray, but the possibility of nongray extinction cannot be excluded because of uncertainties arising from the very small ultraviolet optical depths of the circumstellar dust.

The authors report optical-infrared continuum observations of OJ 287 during its lowest recorded flux level. The spectrum was steeper than previously seen, but does not unambiguously show the presence of any underlying galaxy. It is suggested that this is primarily due to the object's still being too bright to make such a detection in this manner. The authors also report spectroscopic observations of OJ 287 showing the presence of Hα, Hβ, and [O III] emission lines. These lines confirm a redshift z = 0.306. The data are also used to compare the emitted luminosities in these lines to those of other active extragalactic objects. These lines are intrinsically underluminous compared to quasars of similar ionizing luminosities. The data are consistent with OJ 287 being deficient in gas compared to normal quasars or with the observed continuum flux having a Doppler factor of δ ≡ 4.