June, i S o6.| KNAB : GOELDl'S " Os MOSQUITOS NO PARA." 63 



larvae do not prosper in water containing other matter than their essen- 

 tial food, alg?e and other cryptogams. 



The paragraph on mosquitoes as agents of disease reviews what is 

 now known on this important subject and briefly states the part taken 

 by the different investigators in bringing out the facts. The species 

 of mosqu toes that are known to transmit disease are enumerated and 

 the diseases they carry. In the mention of Filaria immitis in the dog, 

 transmitted by Culex fatigans, the writer states that he has found this 

 disease in dogs at Rio de Janeiro and sometimes the left auricle of the 

 heart is filled with a ball of these worms. 



Under the caption " Practical results which urgently claim atten- 

 tion " the various methods of mosquito control are discussed. The 

 baneful effect of mosquitoes is again emphasized, not only as direct 

 agents of yellow fever and other diseases but also as the destroyers of 

 spiritual peace and the producers of neurasthenia through the constant 

 infliction of physical pain. 



Chapter II gives a series of experiments with Stegomyia fasciata 

 and Culex fatigans to ascertain the relation of meals of blood to copu- 

 lation and to oviposition. Upward of 220 adults of both sexes of 

 Stegomyia fasciata and 260 of Culex fatigans were used in these experi- 

 ments. At first captured mosquitoes were used, but later the experi- 

 ments were carried on with bred specimens. The fertilized females 

 were fed with honey and water on the one hand, and with human 

 blood or that of the guinea pig on the other. It is shown that one 

 or more meals of blood are essential to the development of the 

 eggs. Lack of space forbids giving even a synopsis of these experi- 

 ments. It is only possible to give the author's final conclusions, 

 which apply more particularly to Stegomyia fasciata, and state that in 

 general they are borne out by the experiments. In brief his conclu- 

 sions are as follows : 



1. Honey prolongs the life of the mosquito in captivity and is taken 

 with avidity, not only by the female, but above all by the male. 



2. Blood of vertebrates is eagerly and persistently sought by the 

 female ; obtained by sucking it shortens life as further explained. 

 Blood drawn in other ways, although fresh, is refused or accepted with 

 indifference not only by the males but also by the females. 



3. Sucked blood is a food which favors and accelerates the laying 

 of eggs and produces a certain, energetic and immediate reaction in 

 the organization of the female, perceptible from the first ration. 



