MEEK : MOUTH-PARTS OF THE HEMrPTERA. 269 



the lower part is strongly chitinized, and, in connection with 

 the upper, more delicate fold, forms the double-trough-shaped 

 portion already described (fig. 13). This trough-like struc- 

 ture, to continue the homely figure, terminates cephalad by 

 the lower fold suddenly turning upward and forming a prow. 

 From the base of the prow a strongly chitinized tube leads 

 downward and backward, and terminates at the caudal extrem- 

 ity of the epipharynx. 



THE HYPOPHARNYX. 



In dissecting the head from the caudal side, a funnel-shaped, 

 chitinized organ (fig. 3, h) is found at the lower end of the 

 pharynx. This is the hypopharynx. The funnel shape is 

 closely preserved only in the caudal portion, for in front 

 the organ is fused with the pharynx. On each side of the 

 latter the hypopharyngeal lamella extends dorsad, as a thin, 

 chitinized plate (fig. 4, cp) . These plates serve as a support for 

 the large diverging muscles (fig, 3, m.in) already mentioned. 

 The hypopharynx completely hides the tubular, canal part of 

 the pharynx. On its caudal rim the hypopharynx ceases to be 

 chitinous. From this point the tissue continues as a fleshy 

 fold (fig. 14, m) until it passes into the dorsal surface of the 

 labium, where it is again chitinized. The funnel tube sinks 

 into the head and terminates in a tongue-shaped piece at the 

 same point as the conduit from the pharynx. This is the part 

 usually referred to as the true hypopharynx. The lower parts 

 of the chitinous plates just mentioned, near where they fuse 

 with the pharynx (fig. 13, mg) , are fitted with the usual grooves 

 and projections for holding and supporting the maxillae. This 

 structure corresponds to the far more elaborate "Fuhrungslei- 

 sten" described by German writers. In the Cicada they show 

 nothing of the double fold and canal shape described by Geise 

 for the Heteroptera. 



THE SALIVARY INJECTOR. 



Even in the coarse dissections with the needle, it appears that 

 there is a chitinized organ lying in the cavity between the hy- 

 popharyngeal structures and the pharynx. The large converg- 

 ing muscles so prominent in the caudal view (fig. 3, m.in) meet 

 at this point. But little more can be determined without the 

 aid of cross- and longitudinal sections. For this organ I propose 



