Some Habits of the Adults 4 1 



meals. We also know that the Stegomyia cannot 

 transmit yellow fever until twelve days after it has 

 bitten a yellow-fever patient. In one instance it did 

 so fifty-nine days after the last feed. I have kept S. 

 calopus sixty-one days in captivity, or during the most 

 of June, July, and August ; we know that they live 

 for months during the dry season. This does not 

 answer the question as respects other species under 

 normal outdoor conditions. 1 



Buzzing. — Even more aggravating than the bite, 

 although far less serious in its effect (unless influence 

 on nerves, language and feelings, be taken into con- 

 sideration) is the buzz. There is, to the writer, noth- 

 ing on earth so irritating as the shrill piping and 

 shrieking right in one's ear just as one is comfortably 

 drifting off into peaceful slumber. It rouses one up 

 like a fire alarm. The victim snatches wildly at the 

 air, thinking unutterableness, with the general result 

 of a self-inflicted thumped head and the escape of the 

 tiny offender. The buzzing is produced by the vi- 

 brations of a thin shred of chitin in the large air 

 tubes just behind the openings in the thorax which 

 admit the air. The pitch varies with different species 

 as well as with the sexes. Stegomyia is almost a silent 

 mosquito ; being a day flier it would not be good policy 

 for it to attract too much attention. Anopheles will 

 sing at night, but I have never heard it do so in the 

 daytime. As Dr. Howard has stated, the chant of the 

 female Anopheles is of a decidedly lower pitch than 

 that of the other genera, so that the " villain " is 



1 Dupree. 



