Principi was born in
San Mariano, just outside
Perugia, on 4 May 1915, the daughter of Paolina Paletti, and the geologist Paolo Principi (who had been an assistant to geologist
Arturo Issel). Maria graduated in agricultural sciences from the
University of Perugia in 1937, with her
entomology thesis on the Chrysopid
Neuroptera of
Umbria. Later, she earned her PhD at the
University of Bologna.
Career In 1938, she won a scholarship competition sponsored by the Ministry of Agriculture and Forestry. One member of the judging group was the esteemed entomologist
Guido Grandi (1886-1970) who, at the conclusion of the contest, invited Principi to relocate to the University of Bologna and join his institute. There, she was appointed an assistant and in 1951 she earned a teaching qualification in entomology. In her professional research, she studied
Neuropteroids, including the ant-eating insects called
antlions. Principi wrote more than one hundred scientific articles on insects. During the academic year 1959/1960 she supervised the degree thesis
Research on the parasites of three Lepidoptera miners of apple leaves by
Giorgio Celli, who later became a famous Italian ethologist and entomologist, and a politician and television personality. When she retired in 1994 as an internationally renowned scientist, Principi was named
Professor Emerita of the
University of Bologna. == Selected publications ==