The German zoologist Ernst Haeckel (1834-1919) was by far the most influential systematizer and propagandist of Darwinism, but we have long lacked a substantial, scholarly biography, even in German. In its absence, the fragmentary and problematic Anglophone literature has allowed to gain wide currency the caricature that Haeckel was a deviant Darwinian, scientifically insignificant but a forerunner of Nazi race hygiene, a forger, and a fraud. 1 Most historians of German biology long ago made a fairer assessment, thanks especially to Paul Weindling's work. 2 But concerns linger, and Haeckel's public image is dominated by negative stereotypes, especially in the United States. Robert Richards's book attempts a major rehabilitation. Richards amply documents originality, productivity, and significance in support of the claim that "Haeckel was, undeniably, a scientific and even artistic genius" (p. 439). He also insists that, far from being the fount of some illegitimate hybrid of German idealism and evolutionism, Haeckel was an "authentic" Darwinian (p. 100)-indeed, Charles Darwin's most important intellectual heir. Skeptics will doubtless reckon it easier to align