From the 1926 illustrated edition of mythological stories retold as "pastels," or mild erotica, by Pierre Louÿs (Belgian/Fr: 1870 - 1925). It includes Leda, Ariadne, The House on the Nile, Byblis, and Danae. These were written by Louÿs between 1893 and 1898, and were republished as a collection under the title Le Crepuscule des nymphes (Twilight of the Nymphs) after Louÿs' death in July of 1925. In 1926 Bosshard was commissioned to illustrate the collection, the first such commission for the Swiss artist.
A scanned colophon from one of the books found online illuminates the extensive editions of this publication. The translation reads (loosely, in French): "1 copy with research drawings on imperial Japanese paper, numbered 1; 10 copies on Whatman wove with an original accompanying drawing, numbered 2 - 11; 30 copies on Imperial Japon, numbered 12 - 41; 259 copies on velin d'Arches, numbered 42 - 300. Further drawn: 20 on Japanese paper; 15 on chine; 37 hors commerce including one on Whatman reserved for Mrs. Louys, 10 on Japon, and 26 on Velin d'Arches ."