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somewhat like the tip of a hypodermic needle. 

 In cross section it has the shape of an Q, the com- 

 pletion of the tube being formed by the apposi- 

 tion below of the hypopharynx. The labrum is 

 blended with the epipharynx, but does not extend 

 to the tip. 



The hypopharynx is a thin, flat two-edged 

 lamella closely applied to the under surface of the 

 epipharynx. It is pierced by the salivary duct 

 down which the salivary secretion and sporozoits 

 pass. The opening of the duct is continued as a 

 groove reaching almost to the tip of the hypo- 

 pharynx. 



Fig. 43A. Showing relation of Pharyngeal and Salivary Pumps 

 to the Proboscis 



The mandibles are very fine chitinous rods in 

 cross section, crescentic in shape. At the tip of 

 the mandibles are about thirty serrations, though 

 in certain species of Culex these appear to be 

 absent. 



The mandibles are closely applied to the sides 

 of the epipharynx. 



The maxillae are stouter than the mandibles, 

 and fit around the outer side of these and the 



