Deep H $_{\bf \alpha}$ survey of the Milky Way. III. The l = 338 area

The Galactic plane has been observed between l = 337 and l = 342 in the frame of an H Survey of the Southern Milky Way. This area is known to be rich in radio sources but poor in H emission. The analysis of high resolution proles of the H emission observed in this direction nevertheless enabled to distinguish 6 dierent velocity components: 2 faint layers of diuse ionized hydrogen at 0 and 12 km s 1 (VLSR), 2 brighter layers at 28 and 39 km s 1 including individual HII regions, a faint patch at 50 km s 1 and two isolated bright HII regions at 61 km s 1 . Combining these H observations with stellar and radio data we conclude about the most probable distances for the dierent components.