These are also described as “Cap’n Kirk McAllister’s famous algae cakes.” You're looking at the tiny room in which an astronaut spent six months underground as an experiment. Eventually he disappeared, but only after reporting that he could not stop cooing. I am serious.
This was an essential part of all late-60s moonbase scenarios. People would live on algae. Why we would want to build houses on the Moon so we could eat algae and suffer from gas-alien-induced coos was never completely explained. I think this is why the space program suffered that fatal stall - at some point someone said "stop and think, just a minute. We're going to send a man to live for six months in a tiny box underground with nothing but algae cakes to study the effects of eating algae cakes in a tiny box undeground for six months."
Heads nod around the table. "Okay, well, leaving aside the questionable objectives of the study, why do we have to do it on the moon?"
Eyes roll - oh, Christ, here he goes on that "why can't we drive to North Dakota and do it" routine again. But eventually he makes his point forcefully enough, and when NASA draws up plans to build a network of undeground Waffle Houses on the moon, enough people say hey, wait a minute to call the entire enterprise into question.