202 MOSQUITOES OF NORTH AMERICA 



only case we have seen where in Africa a scheme of segregation has been carried 

 out. The result has been to make Victoriaborg reputedly the most healthy 

 European settlement on the West Coast of Africa." 



THE MOSQUITOES THAT CARRY MALARIA. 



JSTo mosquitoes belonging to genera other than Anopheles have been shown to 

 carry malarial diseases of human beings. Culex quinquefasciatus has been 

 shown by Eoss to be the necessary secondary host for a closely allied malarial 

 disease of birds, and other mosquitoes have been shown to carry malarial dis- 

 eases of other animals. At present our knowledge of malarial diseases in wild 

 animals is very slight. With the human species it will probably be ascertained 

 that many, though by no means all, of the species of the genus Anopheles, in its 

 broader sense, transmit malaria. Grassi, Bignami and Bastianelli have proved 

 that in Italy Anopheles maculipenms, A. hifurcaiiLS and A. superpictus trans- 

 mit the various types of malaria. In Japan and Formosa, Tsuzuki deter- 

 mined that Anopheles jesoensis, A. formosaensis and A. cohcesa are responsible 

 for tertian and sestivo-autumnal malaria.* Dr. W. S. Thayer, in his chapter on 

 malaria, vol. 2, part 2, Allbutt & Eolleston's System of Medicine, London, 1909, 

 indicates the following species as having been shown to carry malarial infection : 

 Anopheles hijurcatus (Europe) ; A. maculipennis (Europe) ; A. quadrimacu- 

 latus (North America) ; A. jesoensis (Japan) ; A. martini, A. pursati (Cam- 

 bodia) ; A. vincenti (Tonldn) ; A. listoni, A. culicifacies (India) ; A. funesta, 

 A. super picta, A. paludis (West Africa) ; A. coustani (Madagascar and Ee- 

 union) ; A. costalis (Africa) ; A. cruzii (Brazil) ; A. albimanus (Panama). Ac- 

 cording to Stephens and Christophers Anopheles listoni, A. culicifacies and A. 

 fuliginosus are the species principally concerned in India, and to these A. turJc- 

 hudi has been added and A. jeyporensis is suspected. Kinoshita reports Anoph- 

 eles annulipes as transmitter of pernicious malaria in Formosa. Dr. Arthur 

 Neiva states that in Brazil Anopheles alhimanus, A. argyritarsis, A. pseudo- 

 maculipes, and A. intermedium have been proved malaria carriers. Experi- 

 mental work with Anopheles punctipennis in the United States was begun in 

 1902. Smith in New Jersey, on the 24th of September, caused a number of 

 specimens of the females of this species to bite a patient suffering with malaria. 

 These specimens were later examined by Dr. W. N. Berkeley, of New York City, 

 but vtdthout any definite result. Hirschberg reports the result of comparative 

 experiments with Anopheles quadrimacidatus and Anopheles punctipennis con- 

 ducted by feeding them with the blood of patients known to contain the parasite 

 of sestivo-autumnal malaria. The results were that of 58 specimens of Anopheles 

 punctipennis fed, none were found to be infected, whereas of 48 A. quadrimacu- 

 latus fed, 8 were found to be infected. The same writer pointed out that the 

 distribution of the latter species in the vicinity of Baltimore coincided in a gen- 

 eral way with the occurrence of malaria-infected districts. The disease prevailed 



* According to Kinoshita Anopheles jesoensis = A. sinensis, A. formosaensis and A. coh(Esa = 

 A. listoni. 



