l6 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I39 



two small clawlike structures. In Culex (B) the bar is strongly de- 

 veloped and angulated, its ends, as in Aedes, appear to be attached 

 to the apodemes of the tormae. In front of the bar are two large 

 oval masses of setae curving inward and posteriorly. From above 

 these setal masses two brushes of long hairs project posteriorly. 

 Medially there arise two pairs of short tapering processes that project 

 beneath the bar, and from each angle of the bar a slender, bladelike, 

 sharp-pointed process extends posteriorly. 



The epipharyngeal apparatus of Anopheles as described by Schrem- 

 mer (1949) is again quite different from that of either Aedes or 

 Culex. The bar is V-shaped with an acute angle. Several brushes 

 arise in front of the bar, but particularly developed are two long, wide 

 combs of flattened, sharp-pointed bristles that extend posteriorly 

 from a pair of triangular sclerites in front of the bar. These are the 

 Klingenborsten of Schremmer, who says they are used for cleaning 

 the food particles from the combs of the mandibles. In Anopheles 

 maculipennis, as shown by Schremmer and by Farnsworth (1947), a 

 large muscle from the clypeal region of the head is attached on each 

 end of the epipharyngeal bar. These muscles the writer has not been 

 able to find in Aedes and Culex, but the close connection of the bar 

 with the apodemes of the tormae possibly coordinates the movements 

 of the epipharyngeal apparatus with the movements of the labral 

 brushes. In all three genera a pair of very slender, closely adjacent 

 muscles is attached medially on the bar. Contraction of the lateral 

 muscles of Anopheles, according to Schremmer, protracts the ap- 

 paratus from the epipharyngeal wall, the median muscles are retrac- 

 tors. Thompson (1905) makes no mention of lateral muscles attached 

 on the epipharyngeal bar in Culex, but he notes the presence of the 

 median retractors. 



The mandibles. — Both the mandibles and the maxillae lie on the 

 underside of the head, where they are implanted obliquely in the 

 membranous area that turns upward from the hypostomal margins 

 of the postgenae to the hypopharyngeal bars (fig. 7 B, Md, Mx), the 

 mandibles being above the maxillae. 



The typical culicine and anopheline mandibles are flattened lobes 

 (fig. 5 D,E,F) with their mesal ends produced into strongly sclero- 

 tized toothed processes and a lower seta-bearing lobe. The dorsal 

 margins bear large comblike fringes of long setae directed mesally. 

 The tips of the mandibles on opposite sides do not meet when the 

 mandibles are closed, but come against the hypopharynx, which lies 

 between them (fig. 7 B, Hphy). Each mandible has a posterior basal 



