Notes on the Commoner Species 153 



9. These females may lay eggs which are unfer- 

 tile and do not hatch. 



10. Oviposition finished, the female dies, gen- 

 erally at once ; she may, of course, lay several 

 batches before completing her task. 



1 1. To deposit all her eggs .S. calopus must feed 

 on blood at least two or three times. 



12. The time between eating and laying for 5*. 

 calopus, on the average, is 88.8 hours. 



13. The time from laying to hatching averages 

 4.5 days. 



Dr. Goeldi blames steamers for the spread of .S. 

 calopus, which, with the spread of steam navigation up 

 the Amazon, has gradually appeared and spread the 

 fever through that valley. The males he speaks of 

 as trying to bite, and thinks that they irritate the 

 skin. He remarks that the adult Stcgomyia in cages 

 dance and hum when the late afternoon sun strikes 

 in, the male humming above treble clef, 880 vibra- 

 tions to the second ; the female, at C in the treble 

 clef, 480 vibrations. He seems to think there is also 

 an obscuring octave overtone. S. calopus would not 

 accept reptilian blood ; would bite guinea-pigs, but 

 decidedly preferred man. It did not, as do other 

 mosquitoes, seem to object to draughts, nor even to 

 an electric fan. 



Stcgomyia is of general distribution through the 

 south, and has been reported as far north as New 

 York, where it was brought by steamers, but it will 

 not winter in so cold a climate. In dry seasons, 

 with this, as with many other species, the adults will 

 be dwarfed, so that they can come crawling through 



