monumental investigation of the morphology and biology of the Italian and other European genera of phylloxera. It was a foundation for systematic control of agricultural pests. Helminthology In 1876 Grassi investigated his native hometown Rovellasca for the high mortality of cats and discovered that they were heavily infected with the nematode Dochmius balsami. In 1878, while still a student at the University of Pavia, he discovered anchylostomiasis in Italy from by identifying the eggs from the faeces of infected individuals. He continued to make great impacts on the study of Anguillula intestinalis, filarial worms, Trichocephalus dispar, and Bilharzia. He was the first to show that the human dwarf tapeworm Taenia nana is able to go through its entire life cycle in one animal, without the need of an intermediate host, a notion that had long been rejected. He was also the first to show that the flea Pulex serraticeps is the intermediate host of feline tapeworm Taenia elliptica. Thus he proposed that swallowing of infected fleas (for example, with milk) might be the reason for taeniasis in children. In 1879 he published a work on the life cycle of Strongyloides stercoralis, and erected the genus Strongyloides. In 1890 he, with Salvatore Calandruccio, described Dipetalonema reconditum, a non-pathogenic filarial worm of dogs, and showed that the parasite completed its development in human fleas, Pulex irritans. The first crucial step in understanding the life cycle of the roundworm Ascaris lumbricoides was demonstrated by Grassi in a grotesque self-experimentation. To solve a century-old puzzle of how infection of roundworm is transmitted from one host to another, he ingested the roundworm eggs on 30 August 1879. He had obtained the eggs from a human corpse, which was heavily infected, upon autopsy on 10 October 1878. After twenty-two days, he found fresh eggs in his faeces. Thus proving that the roundworm is transmitted through direct ingestion from contaminated source. Malaria and the life cycle of Plasmodium Grassi made his first contribution on malaria in 1890, when he (with Raimondo Feletti) discovered Haemamoeba vivax, later renamed Plasmodium vivax. He described Proteosoma praecox, the malaria parasite of birds. In 1891 he performed the first inoculation of malaria parasites from one bird into another. He was the first to compile a comprehensive monograph on the identity and impact of different malarial parasites. His work Studi di uno Zoologo Sulla Malaria in 1891 is as relevant today as it