The eighteen Armanen runes were published by Guido von List in 1908. Each is a historical character with his naming and his interpretation on top of it.
The character behind it
Laf corresponds to the Younger Futhark character whose Old Norse name was logr, meaning water, sea or a body of water. The rune poems gloss it as the sea, a waterfall or a stream, and the Old English tradition gives its equivalent a similar reading of water as something one crosses at risk.
What von List did with it
He kept the L value, Germanised the name to Laf, and assigned it a meaning within his own row. His placement of this character also departs from the Younger Futhark order, where the L and M characters fall the other way round. That kind of small rearrangement is one of the reasons the row cannot be treated as a transmitted alphabet: a genuine tradition preserves its order, because the order is how the alphabet is learned.
The frame
Von List presented the eighteen as an ancient Germanic priestly alphabet recovered rather than composed, with its count taken from the eighteen rune-charms of the Havamal. Runologists reject that account.
Reception
The Armanen row was taken up in volkisch circles and by National Socialist organisations during the 1930s and 1940s. The atlas records that documented reception rather than omitting it.