What grammatical usage is exemplified by the phrase 'Numquam huius modī perīculum vīdī'?

The phrase "Numquam huius modī perīculum vīdī" showcases the Genitive of Description. In Latin, this grammatical construction is utilized to provide a characteristic or quality of a noun. Here, "huius modī" describes the type or nature of the danger ("perīculum") being referred to.

The Genitive of Description specifically indicates how the quality of one noun relates to another, distinguishing it by certain attributes. In this example, the speaker emphasizes that they have never seen a danger of this particular kind, highlighting the specific nature of the danger through the genitive form. This usage allows for a more nuanced understanding of the danger being talked about, rather than simply stating it exists.

The other grammatical usages mentioned might relate to different contexts. For instance, the Genitive of Possession would indicate ownership, while the Genitive of Quality refers to a characteristic feature rather than a descriptive quality. The Genitive of Indefinite Value typically expresses a measure or amount rather than a descriptive quality. In this case, the specific context and the way the phrase is constructed affirm that it aptly demonstrates the Genitive of Description.