Lord Howe boobook than both the New Zealand and Norfolk Island subspecies. The Lord Howe boobook was restricted to Lord Howe Island where it inhabited the native forests as well as occurring around the settlements. Exactly when the Lord Howe boobook became extinct is uncertain. Boobook calls were apparently heard on the island until the 1950s, but during the 1920s boobooks from near Sydney in eastern Australia had been introduced, along with barn owls and masked owls, in an unsuccessful effort to control the black rats that had overrun the island. The rats had been accidentally introduced in June 1918 with the grounding
Failure to refer the actual world, according to Russellian logic, most statements in the poem are false. Failure to refer Failure to refer, also reference failure or failure of reference, is the concept that names can fail to name a real object. According to Bertrand Russell's theory of truth, there is only one actual world, and a statement's truth value depends on whether the statement obtains in the actual world. Continuing the tradition of Gottlob Frege, Bertrand Russell posited that a name picks out, or refers to, a real object in the world (Russell's correspondence theory of truth). The name "Genghis Khan" thus