Hubble Space Telescope snapshot survey of 3CR radio source counterparts. III. Radio galaxies with z < 0.1

We present and describe optical counterparts to 46 3CR radio galaxies of re dshifts less than 0.1 that were imaged with the Hubble Space Telescope's (H ST) WFPC2 camera through the broadband F702W filter as part of the 3CR Snap shot Survey. This is the fifth and last such paper describing the 252 radio galaxies of this R-band survey. At the 0."1 resolution of the images, a we alth of detail is visible. Approximately 89% of the galaxies are elliptical s, and nearly all reside in groups or clusters of galaxies of various richn ess and compactness. Nearby elliptical companions of slightly smaller size and mass are common. Dust is prevalent in the cores of the 3C hosts; nearly half of the galaxies possess some type of dust structure, such as irregula r dust lanes, filaments, or disks. Besides the well-known dust disks of 3C 264 and 3C 270, we have found five new candidates in 3C 31, 3C 40, 3C 296, 3C 449, and 3C 465, as well as in the central regions of the nearby neighbo rs of 3C 31 and 3C 465. Our sample includes six confirmed optical synchrotr on jets in 3C 15, 3C 66B, 3C 78, 3C 264, 3C 274, and 3C 371, or approximate ly 13% of the sample. Unresolved nuclei, consistent with the point spread f unction of WFPC2, are found in 43%-54% of the galaxies and in the majority of galaxies with dust disks and optical jets.