Lévy-Dhurmer, a very respected artist during his lifetime, has fallen into relative obscurity these days. His early works have a very beautiful and technically intricate look to them, and very strongly reflect the influence that Pre-Raphaelitism had on Art Nouveau. It's unfortunate he's forgotten these days, because, while not stylistically revolutionary, he nonetheless created absolutely wonderful art pieces.
Fireworks in Venice
Gust of Wind