146 Journal of the Mitchell Society [iV«y 



iiected by many transverse veinlets. Group eight includes our Tropi- 

 (luchina which have a venation quite siniihir to our Dicfijopharina, 

 but costa is distant from the margin of the wing sometimes united by 

 transverse veinlets, and the apical portion of the corium is separated 

 from the basilar portion by a distinct transverse vein, thus paralleling 

 the development of the Heteroptera. 



The Abdomen. Outside of the genitalia the characters of the ab- 

 domen have not been much used. The general shape of the abdomen, 

 whether compressed or depressed is sometimes useful and I have no 

 doubt that other good specific and generic characters await discovery. 

 The abdomen in Fulgoridcn consist of eight definite segments with the 

 ninth, tenth and eleventh segments much modified by the genitalia. 

 Typically each segment consists of the usual tergite, sternite and 

 pleurite. The pleurites are modified in that they usually have a broad 

 lateral portion and a broad ventral portion. The first and second 

 segments are modified by having their tergites ending in a posteriorly 

 directed process from the metapleura. The pleurites are wanting and 

 the sternites are mostly covered by the metasternum, the coxa and 

 trochanters of the hind legs. The spiracles of these segments are 

 situated dorsally well within the lateral margins and the second pair 

 is usually much larger than the first pair. Segments three to six are 

 usually typical with their spiracles on the lateral faces of the pleurites. 

 Segments seven and eight are usually modified by the genitalia but 

 have a pair of small spiracles on the lateral faces of the pleurites. 



The Genitalia. The genitalia are useful in some groups espe- 

 cially in the Delphacina' where the male genitalia are the court of last 

 appeal for specific determinations in many genera. In a few other 

 groups they are frequently useful but in many groui)s they seem to 

 be entirely useless. In the Delphacina the female genitalia are very 

 similar to the female genitalia in other Ilomoptera and consist of a 

 pair of swollen pygofers on either side of the ovipositors. In the males 

 the ninth segment is modified into the tubular pygofer Avhich opens 

 posteriorly through a more or less circular genital aperture which in- 

 cludes the anal segment and the anal style dorsally. Ventrad the 

 aperture is fre(|uently incised to form the ventral sinus, and dorsad 

 there is an incision, the dorsal sinus (anal emargination), which en- 

 closes the anal segment. The angles where the sinuses merge with 

 the genital aperture are sometimes jirolonged and form the dorsal 

 (anal) and ventral angles. In a few cases the ventral wall of the 



