1939] 
Mosquitoes of Massachusetts 
121 
7. Tarsi with pale broad rings especially on hind legs; 
wings scales bicolored 8 
Tarsi with narrow rings; wing scales uniformly dark 
or nearly so 10 
8. Lower mesepimeral bristles absent : excrucians 
Lower mesepimeral bristles present (Fig. 2) 9 
9. With three to five lower mesepimeral bristles ; mesono- 
tum bronzy-brown on the disc, the scales on the ante- 
scutellar space, lateral margins and a sub-dorsal line 
each side of the disc whitish: stimulans 
With two lower mesepimeral bristles; mesonotum with 
a broad median stripe of yellowish brown scales, the 
anterior edge, the sides of the disc and antescutel- 
lar space with yellowish white to white scales i—.fitchii 
10. Last two abdominal segments nearly entirely white 
scaled, venter entirely yellowish white : cantator 
Last two abdominal segments with apical and basal 
bands ; venter with each segment with a median black 
spot or stripe which may be joined to lateral black 
spots forming a Y : vexans 
11. Lower mesepimeral bristles absent 12 
Lower mesepimeral bristles present 17 
12. Mesonotum with silvery scales | 13 
Mesonotum without silvery scales 15 
13. Mesonotum silvery on the sides with a dark brown 
median stripe which widens behind the middle and 
which is divided by the antescutellar space, the ante- 
scutellar space is margined by silvery scales : 
triseriatus 
Mesonotum with a medium silvery stripe reaching scu- 
tellum or entirely silvered 14 
14. Mesonotum with a broad well-defined median silvery 
stripe : atlanticus 
Mesonotum with a narrower poorly defined or diffuse 
median stripe ; mesonotum of male entirely silvery ; a 
very small blackish species : dupreei 
15. Abdomen with a continuous lateral white line ; mesono- 
tum uniformly colored with golden-brown scales, paler 
about the antescutellar space : cinereus 
Abdomen without a continuous lateral white line; me- 
