Final answer:
The 'green trunk' of the Flowerground transport system seems to be a fictional element from a literary work rather than a historical or real-world transportation system.
Step-by-step explanation:
The question pertains to a detailed description of a transport system, which is depicted as part of a story or narrative. Although it mentions a green trunk of the Flowerground transport system, this does not directly correlate with a real or historical transport system but rather seems to reference a fictional or metaphorical element within a literary context. From the given passages, it is evident that transportation has evolved significantly over time, with advancements from horse-driven omnibuses to modern, more sophisticated transport methods.
Additionally, these snippets reflect on different transport methods such as railroads, buses, and automobiles, and their impact on society, with a particular focus on the transformative effect of railroads on perceptions of time, space, distance, and leisure.