Most of the formats of the Petit Trianon Series have a stereotyped decorative pattern on the left of the front cover and one of a number of different floral/decorative patterns on the right half of the front cover. Here is a new pattern for one of the 1897 books. The familiar dots are noted on the left of the cover. This is the 10th different design shown in the database for the right half of the 1897 books.
See: http://henryaltemus.com/series/series141.htm