Report of first expedition to South America, 1913Members of the expedition: Richard PStrong [and others] . long the cracked condition of the clayey surface-soil it isvery plain that in the rainy season there is practically nodry street. At the present time mosquitoes are not veryabundant and this is readily accounted for by the rapiditywith which the rain disappears. Although it rained heav-ily two days ago the streets are dry today. In the pavedstreet in front of the hotel there are numerous large depres-sions containing water due to the large size of the irregularpaving blocks;
Report of first expedition to South America, 1913Members of the expedition: Richard PStrong [and others] . long the cracked condition of the clayey surface-soil it isvery plain that in the rainy season there is practically nodry street. At the present time mosquitoes are not veryabundant and this is readily accounted for by the rapiditywith which the rain disappears. Although it rained heav-ily two days ago the streets are dry today. In the pavedstreet in front of the hotel there are numerous large depres-sions containing water due to the large size of the irregularpaving blocks; these become dry almost twenty-four hoursafter the rain has ceased and on account of traffic cannotpossibly harbor larvae in the rainy season. The water fromthe sewers opening into the street appears to be too dirty forStegomyia so that these must come from receptacles kept inor about the houses. It appears that the opportunities for Stegomyia to breedare in many places limited, but nevertheless this mosquito wasthe commonest species to be observed in the city. In con- lii . «» •» •••? 1. on CQ o o 1-4 o CO I> Xu < ENTOMOLOGICAL INVESTIGATIONS 187 formity with its habits as they have been observed elsewhere,the mosquitoes were not numerous during the day, and wereobserved to bite almost exclusively in poorly lighted rooms,very rarely in a rather bright light. They were very frecjuentlxattracted to a dark hat if it was hung on the wall of a bite mainlj^ about the ankles when there is light. Atnight also they bite most frequently about the ankles, but atthat time about the neck and other exposed parts of the bodyas well. This brings out the fact, already observed elsewhere, that alarge Stegomyia population is not necessary for the main-tenance of a constant incidence of yellow fever in a typical domestic habit of the species coupled with theundoubted great length of its adult life render the si)read ofinfection easy through the agency of
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Keywords: ., bookcentury1900, bookdecade1910, bookidreportoffirs, bookyear1915
