a handbook of the mosquitoes of north america - Systematic Catalog ...

16 MOSQUITOES OF NORTH AMERICA
the genital organs. Arising on each side just beneath the lobe
of the ninth tergite and extending downward and outward and
then curving caudad and dorsad is a dark band of chitin which
ends in a heavily chitinized point and meets, in the median line,
its fellow from the opposite side. This structure constitutes
the tenth segment (Figs. 6, 7 and 8, 10s). The tenth sternite
gives off a short projection (basal arm) near the middle which
articulates with the dorsal arm of the paramere (P). Directly
D.A
FIGURE 7. Dorsal view of the 10th segment, meso-
some and supporting structures of Aedes stimuhas.
Ap. apodeme ; D.A. dorsal arm of the paramere; B.P.
basal plate; D.A.S. dorsal arm of the tenth sternite;
D.B. dorsal bridge ; L.A. lateral arm of the paramere;
Mes. mesosome; P. paramere; 10s. tenth sternite; IOT.
tenth tergite; V.B. ventral bridge.
above the lobes of ninth tergite and partially surrounded by
the tenth segment is the chitinized genital orifice. The ejacu-
latory duct is membranous but it is surrounded by chitinized
plates, the penis valves. In this species the penis valves form
a somewhat cylindrical-shaped organ chitinized on the sides
and over the dorsum. The median ventral portion is not chit-
inized except at the base where there is a complete ring. The
portion over the dorsum has been called the lower bridge, and