ENTOMOLOGY

260 SANITARY ENTOMOLOGYrily in the mosquito. There is indication of a granular stage of development.The optimum temperature for development is 26° C.The earliest suggestions Qf the possibility of mosquito carriage ofyellow fever were made by Josiah C. Nott in 1848, and Dowler in 1855.In 1881 Dr. Carlos J. Finlay made definite claims that the fever is carriedby the bite of a mosquito. In 1900 during the American occupationof Cuba a commission composed of Doctors Walter Reed, James Carroll,Aristides Agramonte; and Jesse W. Lazear began the investigationof the causation of yellow fever by first definitely discrediting the theoryof the Italian bacteriologist" Dr. Giuseppe SanareIli, that his Bacillusicteroides was the cause. This they proved to be identical with Bacillus8ui-pestifer. They then conferred with Dr. Finlay and began a thoroughinvestigation of the mosquito transmission theory. Dr. Finlay suggestedthe common house mosquito, Aedes argenteus (Stegomyia fasciata) asthe cause. The members of the commission submitted themselves to themaking of the tests. Dr. Carroll was the first to take the fever, beingbitten twelve days after a mosquito had bitten a yellow fever patient.In four days he took the fever. A week later Dr. Lazear, while conductingexperiments, was bitten by a mosquito, which he allowed to engorge,but to which he paid little attention. In five days he took the fever anddied in a week. In the course of experiments ten cases of fever were producedat will by the application of infected ~osquitoes, and all otherpossible means of infection proved useless (see Reed, etc.).Dr. Guiteras (1901) confirmed the transmission of yellow fever byAedes argenteus (Stegomyia fasciata) in seven cases, three of whichproved fatal. Later a French commission, Marchoux, ~alimbeni andSimond (1:903) in Brazil, and American commissions composed of Parker,Beyer, and Pothier in Mexico (1903), and Rosenau, Parker, -Francis,and Beyer (1905), corroborated the transmission of the disease by thismosquito. The last named authors tabulate the whole series of transmissionexperiments showing ~hat in 40 cases of transmission by mosquitobite, the incubation period after the bite exceeded three days and afraction in only ten cases, and was possibly less than three whole daysin only two cases. The maximum authentic record o'f the incllbationperiod is six days and two hours.Platyhelmia: It' asciolidaeA Clinostomum is recorded by Soparker (1918) which passes itsfirst stage in a snail, Planorbis e:rustus, and is found as a cercaria in thelarvre and adults of Culea: quinquefasciatus (fatigans) and Anopheles