Final answer:
Professor Hugo's zoo is a collection of creatures from different planets, including three-legged creatures from Venus, tall, thin men from Mars, and horse spiders from another planet.
Step-by-step explanation:
Based on the information provided, Professor Hugo's zoo can be described as a collection of various creatures from different planets. It includes three-legged creatures from Venus, tall, thin men from Mars, and horse spiders from a distant planet. This zoo showcases the diversity of life forms from other planets and provides a unique opportunity for people to observe and study these extraterrestrial species.