GALACTIC WORMS .1. CATALOG OF WORM CANDIDATES

We have found and cataloged 118 isolated structures that appear both in H I and in infrared (60 and 100-mu-m). In the inner Galaxy, these correspond to the "H I worms" detected by Heiles. The worms are thought to be the walls surrounding superbubbles which have broken through the thin gaseous disk inside the solar circle. Among 118 structures, 52 are possibly associated with H II regions. The structures associated with H II regions have a higher probability for association with superbubbles. Upon analysis of the catalog, we found that (1) the 100-mu-m emissivity, I100/N(H I), increases systematically toward the Galactic interior, which is consistent with the increase of the general interstellar radiation field, (2) the 100-mu-m emissivity of the structures associated with H II regions is larger than that of the structures without associated H II regions, and (3) the 60-100-mu-m ratio is large, 0.28 +/- 0.03, which may indicate that the grains associated with atomic gas have a relatively large population of small grains. Among 118 structures, 35 appear in the 408 MHz continuum. About 70% of the 35 structures are possibly associated with H II regions. The infrared and the radio continuum properties suggest that the 408 MHz continuum emission in those structures is very likely thermal. The thermal emission probably originates from the gas ionized by photons from stars located in the same general region that produce the H II region. Some individual objects are briefly described. We discuss implications of our results on the ionization of gas far from the Galactic plane.