SO WAM Rob E 
_ 
11, 
12. 
13. 
14, 
15. 
EXPLANATION OF Puate II. 
. Side view of head of Culex, with extended mouth-parts; @, antenne. 
Same from above with mouth-parts partly cut away. 
Tip of labium of female Culex. 
Tip of labium of male Cuwlez. 
Tips of separated sete of mouth-parts of Culez. 
Tip of labrum-epipharynx seen from beneath and in section. 
. Cross-section through labelle and tip of labium of female Culez. 
Cross-section near middle of the proboscis of female Culez. 
Cross-section through pharyngeal region of forward part of head of female Culez. 
. Cross-section through posterior part of head of female Culez, to show the sucking 
bulb of the esophagus. 0b, lumen of esophageal bulb; bm and bm’, muscles to 
dilate the bulb; 7, chitinous rods which support the wsophageal bulb; rm, 
retractor muscles of maxille, at their point of origin; t, elastic plates of sides 
of bulb. 
Longitudinal section of head of a female Culex. b, esophageal bulb; g, point 
where the clypeus appears cut off from rest of head; v, valve between pharynx 
and esophagus. 
Cross-section near middle of the proboscis of a male Culez. 
Cross-section at base of the proboscis of a male Culez. 
Cross-section further into the base of the proboscis of a male Culez. 
Cross-section through pharyngeal region of head of a male Culez. 
The following letters have the same signification throughout : 
ce, clypeus. Ir, labrum. p, pharynx. 
e, epipharynx. Ire, labrum-epipharynx. pm, pm’, pharyngeal muscles. 
h, hypopharynx. , mandibles. &, supracesophageal ganglion. 
i, infrewsopiagedl ganglion. wh maxillary palpi. tr, tracheal stem. 
i, labium, me, maxille. 
1b, labelle. oe, cesophagus. 
36b 
