Stephen Jay Gould has written more than one wonderful essay debunking weird ideas about recapitulation (Pervasive Influence especially comes to mind), which includes examining and rejecting Ernst Haeckel's bizarre concepts. (Gould's writings were not referenced anywhere in that linked article, which probably shouldn't have been much of a surprise.) And Gould accurately pointed out that the stupid Haeckel drawings kept being reproduced in textbooks right up through the 1960's and 1970's. But the reason why Haeckel's ideas were so popular in the first place is that like those of Brinton, Cope, Vogt, Crofton, Serres, and a host of other 19th century scientists, they formed an appealing "scientific" explanation for the racism of that era. (And that explanation is a whole different thread...) So none of this has anything to do with the accuracy of "evolution."