How does Impressionism in the 1870s compare to Post-Impressionism in the 1880s and 90s?

Post-impressionism was relevant from title="Post-Impressionism. James Voorhies. Department of European Paintings, The
Metropolitan Museum of Art"
href="http://www.metmuseum.org/toah/hd/poim/hd_poim.htm">1880-1920. The
term was coined in 1910 and was used to describe a younger group of artists who embraced
the vivid colors of the impressionists, but rejected what they considered to be
unstructured forms and trivial subject matter.  One typically thinks of Monet, Renoir,
Cassatt, Morisot as the "founders" of the Impressionist movement; their works were
characterized by romantic landscapes and portraits, often of attractive people enjoying
leisure activities.  They favored visible brushstrokes and chunky applications of paint,
often in many layers.  The post-Impressionists tend to bring to mind artists like
Pissarro, Gauguin, Van Gogh, Seurat, and techniques such as Pointillism (using tiny dots
of color on the canvas), and bold, structured shapes that eschewed any remnant of the
messy brush strokes of the Impressionists.  Although many post-Impressionist artists
worked and/or exhibited together on occasion, they were not in agreement artistically on
much of anything, other than the rejection of the work of the first
impressionists.