390 NEW YORK STATE MUSEUM 



ciliated with hairs, by means of which a current of water is 

 produced that brings little particles of food within reach. 

 At the posterior end of the body is usually a single breath- 

 ing tube, or there are two tubes opening to the exterior on 

 the dorsal surface of the last segment. The segment behind the 

 head is without prolegs. 



The pupae are free swimming, and very active. The breath- 

 ing tubes are situated at the sides of the thoracic segments. 

 The abdomen terminates in two leaflike appendages, that act 

 as projjellers; but in general the pupae remain near the surface, 

 except when disturbed. 



KEY TO GEXERA OP CULICIDAE OP THE NORTHERN STATES 



Larvae 



1 The last abdominal segmeut with a siugle dorsal breathing 



tube, through which may be seen a pair of large tracheae (4) 



Last segment without long breathing tube, (2) 



2 Last segment dorsally with a flat area in which may be seen 



two spiracles (3) 



Last segment usually with hoolvs, no spiracles apparent. 

 Larva transparent, glasslike Corethra 



5 Large species "n-ith the anal segment bladderlike. Mandibles 



strongly developed [pl.41, fig.ll Pelorempis, gen. nov. 



Species of medium size with anal segment cylindrical. ..Anopheles 

 4 Antennae pendant and ending with four large curved spines. 



Mochlonyx (Europe) 



Antennae not pendant (5) 



C Antennae fold back against head and terminate in 2 or 3 



claws [pi. 40] Corethrella 



Antennae usually only with a few small erect bristles and 

 one or two pointed processes (6) 



6 With brush of hairs projecting forward from the mouth (7) 



Binish projects laterad from the mouth. Mandibles long and 



shax-ply toothed; large species about 10mm long 



Psorophora (ciliata) 



7 No ventral brush on last abdominal segment (10) 



Last segment with ventral brush (8) 



8 Anal blood gills dilated; lateral comb of eighth segment a 



single transverse row of spines with elongated bases; anal 



segment without hair tufts before barred area 



Stegomyia (fasciata) 

 Anal blood gills slender (9) 



9 Anal blood gills sharply pointed, air tube spines with one 



tooth; lateral comb of eighth segment a few large spines 



In a single or partly double row A e d e s (fuscu?) 



Not as above in all respects C u 1 e x 



