"Cometary" globules and the structure of the Gum nebula.

Tailed, comet-like objects found in the outskirts of the Gum nebula (and elsewhere) are shown to be > I0 yr old. This implies that the H ii region is much older than the Vela Pulsar 0833-45. Tailed structure found in NGC 5367 suggests the presence of ionized hydrogen falling into the galactic plane near 1 = 320