No questions this week, but there was one thing that tripped me. I’ll share it here, in case others get the same question when they read the chapter sometime in the future:
page 71
飛来せし時
せし is a classical form of した (past tense of する). It is an old grammar point that is not used anymore in modern Japanese. Since 記憶細胞 is talking about a legend that has passed over generations for a long time, I suppose using せし makes the legend really feel old.