Historia Naturalis Palmarum

"The author of over 150 botanical titles, including the great flora of Brazil, Karl Friedrich Philipp von Martius also wrote the still-definitive three-volume treatise on the palm family, one of the first plant monographs. He developed his life-long fascination with palms during an expedition through Brazil [map] from 1817 to 1820, and he worked nearly 30 years to prepare this grand summation, including palms found only as fossils." [source]

All three volumes of 'Historia Naturalis Palmarum' are available at the Botanicus website from the Missouri Botanical Gardens. This lavishly illustrated series included systematic descriptions of all known species in the palm family (Arecaceae). The illustrations were produced by Martius himself and Ferdinand Bauer (among others).

You can get an idea of how enormous the available jp2 image files of each chromolithograph are by clicking on those couple of illustration details towards the end of the sampling above. [each image file is about 3Mb and converts to ~20Mb jpeg files] Mouse over the images - taken from all three volumes - for the botanical names (in most cases).

• Wikipedia: FP von Martius; Historia Naturalis Palmarum.
  
• Biography at Botanische Staatssammlung München.
  
• The Martius Project.
  
• Flora Brasiliensis [previously on BibliOdyssey]
  
• Simiarum et Vespertilionum from JB von Spix (the zoologist who accompanied Martius on the Brazilian expedition).
  
• Thanks Joao!
• UPDATE: The book has now been rereleased by Taschen