Haemoproteus insects including mosquitoes, biting midges ("Culicoides"), louse flies ("Hippoboscidae") and tabanid flies ("Tabanidae"). Infection with this genus is sometimes known as pseudomalaria because of the parasites' similarities with "Plasmodium" species. Within the genus there are at least 173 species, 5 varieties and 1 subspecies. Of these over 140 occur in birds, 16 in reptiles and 3 in amphibia: 14 orders and 50 families of birds are represented. These include gamebirds ("Galliformes"), waterfowl ("Anseriformes"), raptors ("Accipitriformes", "Falconiformes", "Strigiformes"), pigeons and doves ("Columbiformes"), and perching birds or songbirds ("Passeriformes"). The first description of this genus was in 1890 by Kruse who described
The Origin of Birds exquisite detail the fossil remains of several extinct birds, including "Hesperornis", "Ichthyornis", "Archaeopteryx", and ""Archaeornis"", the name used commonly at the time for the Berlin specimen, which was then thought to represent a separate genus. Throughout this section are many finely detailed and labeled renderings of different parts of the skeletal anatomy of these birds, as well as other groups of extinct reptiles and some modern birds. Heilmann's attention to detail in his artwork is inspired at least in part by his dissatisfaction with anatomical renderings of these animals in scholarly works of the time, which he deemed as "unsatisfactory"