Nearly every plate in Kunstformen der Natur depicts invertebrates, protists, or plants — Haeckel's own research specialties — which makes this crowded, jewel-toned study of hummingbirds (Trochilidae) an outlier in the best way: a rainforest canopy dense with a dozen species shown mid-flight and at rest, iridescent throat feathers picked out in metallic color the lithographic process pushed to its limit. Haeckel included it precisely because hummingbirds made his underlying argument almost too easy — few living things display color and form as ostentatiously patterned as these birds, direct evidence, in his view, of nature's aesthetic order extending even to warm-blooded vertebrates. What to notice: a nest with two eggs tucked at lower left is the plate's only still moment amid constant motion — the ordinary domestic fact underneath all that iridescent display.

Maker: Ernst Haeckel (lithograph by Adolf Giltsch)
Date: 1899–1904
Medium of the original: Lithograph
Original held by: Wikimedia Commons
Credit: Wikimedia Commons
Rights: Public domain, verified
Catalogue number: PA-00273

As chosen: 8 x 12 in, art print, classic frame
Picture	8 x 12 in
Outside size	9.6 x 13.6 in
Depth	0.9 in (22 mm)
Weight	[[REAL PROOF NEEDED: shipped weight per size and frame]]
Hanging	[[REAL PROOF NEEDED: hanging hardware Prodigi fits to this frame]]
Material	Enhanced matte art paper, 200 gsm; acrylic glazing
Made in	Charlotte, North Carolina, by Prodigi

Before a size goes on sale, the file is measured against it: pixels per inch at that size, how much of the picture a crop would lose, tone and sharpness. A size that fails is not offered, so there is nothing to choose wrong.

How the print check works

Sizes offered
Size	dpi	Grade	How it fits
8 x 12 in	183	Good	Trimmed 6.5%

Sizes withheld
Size	Why
8 x 10 in	Wrong shape: a 11% crop
11 x 14 in	142 dpi; a historical scan is never enlarged
12 x 16 in	130 dpi; a historical scan is never enlarged
12 x 18 in	122 dpi; a historical scan is never enlarged
16 x 20 in	Wrong shape: a 11% crop
16 x 24 in	91 dpi; a historical scan is never enlarged
18 x 24 in	87 dpi; a historical scan is never enlarged
20 x 30 in	73 dpi; a historical scan is never enlarged
24 x 30 in	Wrong shape: a 11% crop
24 x 36 in	61 dpi; a historical scan is never enlarged
30 x 40 in	52 dpi; a historical scan is never enlarged
36 x 48 in	43 dpi; a historical scan is never enlarged
40 x 60 in	36 dpi; a historical scan is never enlarged