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ENTOMOLOGICAL SOCIETY 



base of the last joint extend three strong bundles of muscles, 

 which attach the labium to the base of the head on either side 

 and to the prosternum. The upper surface of the labium is 

 deeply grooved, forming a channel which encloses the two pairs 

 of setae. 



The base of the labium is supported by a tongue-like expan 

 sion of the prosternum (V #), which is concave on the anterior 

 face, so as to receive and strengthen the basal joint of the labium. 



Epipharynx. What I deem the epipharynx is a keel-like 

 structure (fig. 23, I d and I' d') projecting from the centre of the 



FIG. 23. Head and prothorax of Cicada, lateral view, with parts separated to 

 show structure. See text for full description (original). 



roof of the mouth, attaching to the clypeus and labium. It is 

 rather chitinous and glistening, and the edge is slightly roughened 

 or serrate from the presence of a row of minute depressions or 

 foveae.* The inner lobes of the mandibles close up against the 

 epipharynx on either side. 



Hypopharynx. This is a small, tongue-like expansion (IV 

 </), forming the upper face of the labium or the floor of the 

 mouth, and projects apically as a short, free cylindrical tongue 



* This seems to be the so-called gland attaching to the labrum men 

 tioned by Professor Smith. 



