NO. 3557 SUBGENUS CULEX—BRAM 9 
the nomenclature of Freeborn and Bohart (1951) is utilized through- 
out this study. Following is a brief discussion of major morpho- 
logical characters of the male terminalia utilized in this study. Each 
structure discussed is included in diagrams of each species. 
Tenth sternites (XS): These structures were regarded by Chris- 
tophers and Barraud (1923) as the cerci united with the anal lobe, 
but in general taxonomic nomenclature they are recognized as 
sternites. In the subgenus Culex the tenth sternites are crowned 
with a tuft of spines and it is this character that is considered im- 
portant. Three basic arrangements of tufts are found and can be 
readily identified: (1) spines sparse and weak; (2) spines dense and 
rather strong; and (3) spines dense and strong apically, but with the 
spines on the outer lateral margins spatulate and rather scalelike in 
appearance. It should be noted that all species exhibiting arrange- 
ment ‘‘(1)’’ do not possess a leaf on the apical lobe of the basistyle; 
however, the reverse is not true. 
Ventral cornu (VC): Stone (personal communication, 1962) con- 
sidered this structure to represent a modification of the apical tooth 
of the median process of the mesosome. ‘Two rather distinct con- 
figurations can be recognized. Most species possess a dentiform 
ventral cornu, although the structure may assume a variety of shapes 
and sizes in relation to the teeth of the median process of the mesosome. 
A second form exists where the ventral cornu is very large, rounded, 
and exhibits rugulose outer margins. 
Median process of the mesosome (MP): The precise number of 
teeth on the median process of the mesosome varies somewhat, even 
within a species. Three recognizable situations, however, seem to 
exist: (1) the teeth are absent or are, at most, one or two in number; 
(2) the teeth are distinctly separated and range in number from three 
to approximately 10; and (3) the condition in which a large number 
of conglomerate teeth is present. 
External process (EP): This structure issues from the center of the 
mesosome and assumes various shapes and sizes in relation to the 
median process of the mesosome. The structure is present in all 
species of the subgenus, but is difficult to distinguish when the termi- 
nalia is mounted in the everted position. 
Basal arm of the mesosome (BA): This structure generally issues 
from the mesosome as a short, straight, bluntly rounded limb. In 
some species the structure may be completely absent, and in other 
species it may be bent at an acute angle so as to be directed posteriorly. 
Apical lobe of the basistyle (AL): There is great variation in setal 
arrangement on the apical lobe, as well as variations in the conforma- 
tion of the lobe, itself. Lane (1953) conveniently divided the sub- 
genus into two groups, depending on whether or not the apical lobe 
