branch: biology of Kansas membracid^. 91 



In a section near the tip of the beak (fig. 46, pi. XIII) the 

 groove is shallow and opens in front, allowing the setae free 

 and unhampered movement. In this section the maxillary set« 

 are found, as they are longer than the mandibular setae, which 

 do not always extend to the end of the beak ; in fact, the max- 

 illary setae are frequently a full mm. longer than the beak. In 

 this third segment the shape near the tip is circular. The 

 supporting rod is not visible in the figure, but the dorsal wall 

 is indentated slightly in the middle, and the rod probably plays 

 in this indentation. The maxillary setae here appear as one, 

 but upon closer observation this structure appears to be made 

 up of two sections tightly grooved on their inner surfaces. 

 One seta is situated above the other throughout the entire line 

 of the beak. 



A section near the middle of the third segment is shown at 

 figure 45, plate XIII. Here the shape is elongated dorso-ven- 

 trad. (Fig. 38a, pi. XI.) In this section we notice the pres- 

 ence of the mandibular setae ; they are crescent-shaped, folding 

 around the maxillary setae. As the sections proceed toward 

 the head, the labium becomes more circular in shape until near 

 the upper end of the second segment it seems to be almost a 

 perfect circle. (Fig. 44, pi. XIII.) A clearer conception of 

 the various parts may be seen in figure 43, plate XIII. The 

 shape is elliptical laterad and the strengthening rod is very 

 clearly present. The epipharynx completely closes the tube and 

 protects the setae. The mandibular setae show an opening 

 which has been noticeable in the other sections. The shape of 

 the setae is circular on its outer edge, but on the inner edge it is 

 triangular. (See e, fig. 43, pi. XIII.) The ventral curve folds 

 around the maxillary setae. The maxillary setae show the 

 grooved structure on their inner edges. 



By making observations on figure 38a, plate XI, the reader 

 will ascertain that a cut made transversely on the beak will 

 also cut transversely, or nearly so, across the mandibular and 

 maxillary sclerites. Such a section is shown at figure 47, 

 plate XIII. The setae have become much larger than they were 

 in the beak. The maxillary setae have separated from each 

 other (.T and d, fig. 47, pi. XIII). The clypeus shows its vari- 

 ous braces and pharyngeal muscles. 



In a longitudinal section — that is, across the vertical plane — 

 the cut will be parallel to the longitudinal line of the maxillary 



