Half title of Picturesque New Guinea (1887), with ornamentation above and below the title
The half title, or bastard title, is a page carrying nothing but the title of a book—as opposed to the title page, which also lists subtitle, author, publisher and similar data.
The half title can have some ornamentation of the book's title, or it can be plain text.
Theodore Low De Vinne distinguishes between half title and bastard title in his series The Practice of Typography, saying:
The half-title should not be confounded with the bastard title. The half-title follows the title and begins the first page of text; the bastard title, usually a single line in capital letters, precedes the full title, and takes a separate leaf with blank verso.