THE COM^roX .MOSQUITOES OF MINNESOTA 77 



TABLE TO DETERMINE MOSQUITO LARVAE 



A. No breathing tube on eighth abdominal segment. Lie parallel to sur- 

 face of water. 



Anopheles puneiipcnms 

 Anopheles quadrinmculattts 

 AA. Breathing tube present on eighth abdominal segment. 



B. Scales on eighth abdominal segment not more than sixteen in 

 number. 



C. Breathing tulie three times as long as broad or longer. 

 D. Larva fairly large, breathing tube stout. 



E. Twelve elongate scales in a single row on 

 eighth abdominal segment. Twelve to sixteen 

 spines on breathing tube, each with one mod- 

 erate tooth, and sometimes a few smaller ones 

 below. 



Aedcs fiiscus 



EE. Ten to fifteen scales in a partly double row 



tapering apically; fourteen to eighteen spines 



on lireathing tube, simple or with two or three 



teeth. 



Aedes syk'estris 

 DD. Larvae small, about one-fourth of an inch long; 

 breathing tube slender, at least five times as long as 

 broad. 



Aedes anroides 

 CC. Breathing tube very short and pointed, fitted to puncture 

 plant roots to which larva remains attached. 



Mausouia perturhans 

 BB. Scales twenty or more in numl:)er, forming a large patch. 



C. Breathing tube short, not more than twice as long as broad; 

 scales on eighth alidominal segment fourteen to twenty- 

 two in number, with stout apical and slender lateral spines 

 with two or three serrations, sometimes simple. 



Aedes trizi flatus 

 CC. Breathing- tube moderate, two and one-half to three and 

 one-half times as long as broad; scales twenty-five to fifty 

 in number with small apical and smaller lateral spines; six- 

 teen to twenty-four spines on breathing tube with four or 

 five serrations on basal half. 



Aedes eanadensis 

 CCC. Breathing tube not less than four times as long as broad. 



D. Breathing tube of moderate length, sides a little in- 

 flated. 



E. Tracheal gills moderately long; tuft on anten- 

 nae at or before middle of length. 



Culex pipiens 

 EE. Tracheal gills rather long; tuft on antennae be- 

 3-ond the middle of the length. 



Culex restuans 

 DD. Breathing tube very long, five times as long as wid- 

 est diameter. 



Aedes ahfitehii 



Culex pipiens Linn — The House Mosquito. 



This extremely common mosquito was probably introduced into 

 North America from Europe and is always closely associated with 

 man, being; seldom found far from his habitation. It is a city form, 

 being- more often represented in rural districts by its close relative, 



