Our dog is the gentlest, most saintly of creatures, except if you’re an opossum. He has grabbed five of the nocturnal marsupials in our backyard and killed at least three of them. The others feigned death, we suspect, and later got away. I’ve watched Luke shake opossums by the neck until something audibly cracks, and heard the crunching of their skulls in his jaws. While reading up on opossums – in part, to confirm they can’t carry rabies -- I noted a South American species, the white-bellied slender opossum, known by the scientific name Marmosops noctivagus. The origin of the genus is evident but something about the species name rang a distant bell.
The OED defines noctivagous as an adjective meaning “that wanders or roams about at night,” which is scientific but also suggests a ghost story. A related adjective is the equally rare noctivagant. In 2009 I read Monsignor Ronald Knox (1959), Evelyn Waugh’s biography of his friend and the author of one of my favorite books, Enthusiasm: A Chapter in the History of Religion (1950). Waugh quotes a 1901 letter Knox writes to his sister Ethel:
“I am dying to know how your photograph of me gracefully propped like a belated noctivagous reveller against the corrugated lithological specimen in the garden of our delightful country residence so exquisitely named in the sonorous nomenclature of our somewhat verbose Cymric neighbours Glan Gwynnant, has come out in printing.”
Knox was thirteen when he wrote this, and I had to look up “noctivagous.” Waugh tells us Knox’s letters from Eton were “often humorous in intent, alternating a parody of nursery speech and an extravagant pedantry.” While still a boy, his language could be downright Firbankian. That’s why I copied the sentence into a commonplace book. Waugh goes on to quote a letter Knox wrote to his mother in 1902:
“I went around Windsor Castle without seeing a single chair I should like to sit on. A throne there had a sort of chevaux de frise to stick into the back of one’s knees. One might make a rhyme out of that.”
In a similar Knoxian spirit, the OED cites another use of noctivagous, this one by the Rev. F. E. Paget, a supporter of the Oxford Movement, in The Pageant (1843): “Beasts of prey, burglars, and ladies of fashion are the only three kinds of noctivagous mammalia.” Opossums are New World creatures.