Portrait of Camille Mauclair, 1896

Kate de Rothschild features this portrait of Camille Mauclair on her "Master Drawings" page, and informs us in the biographical sketch that Mauclair published his Sonatines d'Automne (Autumn Sonatas) in 1894, about the same time that Levy-Dhurmer began his famous series of autumn scenes.  One may deduce that the autumn series of 1896-1897 was, in fact, inspired by Mauclair.

From Wikipedia: Camille Mauclair

^"Séverin Faust (December 29, 1872, Paris – April 23, 1945), better known by his pseudonym Camille Mauclair, was a French poet, novelist, biographer, travel writer, and art critic.

"Mauclair was a great admirer of Stéphane Mallarmé, to whom several works were devoted, as well as Maurice Maeterlinck. He was initially a poet and novelist. His poetry attracted some attention, and was set to music by Ernest Bloch, Gustave Charpentier, and Ernest Chausson and Nadia Boulanger.

^"His best-known novel is Le Soleil des morts (1898), a roman à clef containing fictionalized portraits of leading avant-garde writers, artists, and musicians of the 1890s, that has in retrospect been seen as an important historical document of the fin de siècle. He also wrote several non-fiction books about music including Schumann (1906), The Religion of Music (1909), The History of European Music from 1850-1914 (1914) and The Heroes of the Orchestra (1921) which contributed greatly to French awareness of musical trends

References

Mauclair, Camille. Sonatines d'Automne. (Perrin, 1895). Selections published by Claude Torres.
Mauclair, Camille.  The French Impressionists (1860 - 1900).  Project Gutenberg ebook 
Mauclair, Camille. Le Soleil Des Morts. (Slatkine, 1979 edition in French).  Google Books.

Two poems by Camille Mauclair at Black Cat Poems
Poem "The Lying Sun" at Forgotten Shelves