Automatic bookmarker band

An automatic bookmarker for use in combination with a book having pages, a book cover, and a dust jacket over the cover, the dust jacket having an inwardly folded flap positioned between the pages and the cover, said bookmarker comprising a plate-like member having means for securely engaging the inwardly folded flap of the dust jacket, and a yarn-like band of elastic material fastened at each of its ends to said plate-like member and extending diagonally with respect to an upper edge of said plate-like member which extends in parallel to an upper edge of the dust jacket whereby when the plate-like member is engaged with the flap of the dust jacket between the cover and the pages of the book, the yarn-like band can be stretched over a corner of any given page of the book.