This scientific guidebook offers an organized overview of the collections held at the Civic Museum of Natural History of Milan, based on its state as of the early 1970s. Authored by Claudio Conci, the fourth edition (1972) outlines the museum’s key departments—including zoology, mineralogy, paleontology, and botany—presenting their historical development and educational function. Designed for both general visitors and specialists, the guide highlights notable specimens, exhibition logic, and classification systems, making it a functional resource for navigating the museum and understanding its scientific value in a broader cultural context.