Here's a classic example of Marsh's grim, shadowy scenes, from TARZAN #18 (1950). He takes advantage of this sunset scene to revisit a solitary, melancholic mood that often surfaces in his work. Stark, broad areas of black dominate the page, and the hero's face is constantly masked in shadow.
Notice also how the apes' backs are continually turned toward Tarzan, isolating him. In addition, nowhere on this page does Tarzan occupy the same visual plane with his ostensible brothers. First he is upright, standing above them, while they are lateral... then he is alone... then he is upright beneath them, while they remain lateral... then he exits the frame without them... then he's standing among the foliage, while one clings to the cliffside, apart from him... then he stands alone against the sky, while one occupies the foliage, turned away from him. Where other artists would depict a team effort, Marsh shows us a stranger in a crowd.
Such doleful visuals rarely appeared in other '40s & '50s adventure comics, but in Marsh's oeuvre, characters often find themselves alone and in darkness. A suitable legacy for the confirmed bachelor who worked anonymously, and died blind and alone.
Also notable here is the writing, by Gaylord DuBois. The apes accompany Tarzan on his mission to rescue some women... but upon seeing food, they are quickly sidetracked, and Tarzan must proceed alone. By giving his apes such short attention spans, DuBois was able to distinguish them from humans and compensate for the unreality of their ability to speak.