The spectrum of neutral actinium has not been reobserved since the early work by Meggers, Fred and Tomkins (57.3). Eighty-seven lines are classified as transitions between six even and thirty-four odd levels. New progress in the analysis will not be possible from a few tens of lines which remain unclassified between 296.8 and 786.6 nm. The search for the lowest odd configuration 7s²7p, will require extended observations in the red and infrared regions.