One of the typefaces in Griffith’s “Legibility Group” for Linotype, including Corona, Excelsior/Opticon/Paragon, Ionic No. 5, and Textype.

“Related typefaces Opticon and Paragon were released in 1935 as slightly heavier and slightly lighter versions of Excelsior designed for newspapers that deliberately underink to favor halftones, or overink to favor text and headlines.” — The Legibility of Type via Wikipedia