case P. claviger. By today's standard, they are likely to have shared the Nobel prize. Grassi's law Grassi had developed a dogma that "there is no malaria without Anopheles" or simply, "anophelism without malaria". This was dubbed "Grassi's Law", which is formulated as: infected man + anopheles mosquitoes = malaria. Although the equation is straightforwardly correct, the reverse implication is not so. In many areas, he himself had noted that where anopheline vectors were abundant, malaria was not at all prevalent, and sometimes absent. This caused a little problem in understanding malaria epidemiology for some time. In fact, in 1919 he identified three typical malaria-prevalent localities which were not affected by malaria in the same way: the gardens of Schito near Naples, Massarosa in Tuscany, and Alberone in Lombardia. In 1921, after repeated assessment, he concluded with the assumption of the existence of races of Anopheles that there were morphologically indistinguishable mosquitoes that do not bite humans and therefore did not play a role as vectors. The enigma was solved in 1925, a year after his death, by his pupil Falleroni, who demonstrated that there are six cryptic species, of which only four bite humans and transmit malaria. Recognition Grassi was awarded the Royal Society's Darwin Medal in 1896 for his contribution to the study of termites. He was made a senator in Italy by King Victor Emmanuel III. A stamp commemorating Grassi with his portrait on it was issued by the Italian post office in 1955. His birthplace in Rovellasca has been turned into a social centre for the elderly, the front wall of which bears his bust, underneath which there is an inscription: IN QUESTA CASA DEI SUOI AVI NACQUE IL 27 MARZO 1854 BATTISTA GRASSI MEDICO E MAESTRO SCIENZIATO E FILOSOFO CONTESE ALLA BIOLOGIA I SUOI SEGRETI NE TRASSE ARMI CONTRO LA FEBBRE PALUSTRE INVANO COMBATTUTA DA SECOLI MORTO A ROMA IL 4 MAGGIO 1925 VOLLE ESSERE SEPOLTO A FIUMICINO FRA GLI UMILI LAVORATORI DELLA MAREMMA E DELLA PALUDE DI CUI AVEVA INIZIATO LA REDENZIONE I SUOI CONCITTADINI DEDICANO LAPIDE RINNOVATA E ONORATA NEL I° CENTENARIO DELLA NASCITA MENTRE NEL MONDO SI AVVERA IL SUO SOGNO D'UMANA REDENZIONE DAL SECOLARE FLAGELLO MALARICO 27 MARZO 1954 [Translated as: IN THIS HOME OF HIS ANCESTORS/27 MARCH 1854 WAS BORN/BATTISTA GRASSI/PHYSICIAN AND EXCELLENT SCIENTIST AND PHILOSOPHER/ CONTENTIONS TO BIOLOGY /HE TOOK ARMS AGAINST MARSH FEVER/UNSUCCESSFULLY FOUGHT FOR CENTURIES/DIED IN ROME