49 



sexes, the vertex l)eiii<>' sliar])l_v iiuiiiihir ;it a))ex and the keels 

 of face eoiitii>iioiis from base. 



Stramineous; tegmina hyaline, a fuscous mark from base of first 

 median sector down median cross vein and up second cubital vein, 

 forming a wide V marlt, fuscous mark on vein in middle of subcostal 

 cell, faintly infuscate in apical cells and over apical cross-vein be- 

 tween first sector and first cubital vein. 



^ , Ventral edge of pygophor truncate, lateral edges dorsally curv- 

 ing to base of anal segment; anal segment with the apex produced 

 into a long spine which is turned down at right angle to basal portion, 

 basal portion a little longer than broad, subparallel-sided, anus near 

 middle; genital styles reaching to the end of the broad portion of 

 anal segment, apices rounded with a slight emargination, bent upward 

 at a right angle near middle, a rounded projection on the lower edge 

 near angle. 



9 . Last ventral plate of abdomen slightly and angularly produced 

 in middle; anal segment very small, narrowed towards rounded apex. 



Iveiiii'th '2.') null. ; leiiiuen (i. nun. 



Hal). Mt. Ari, Forinosa, October (]\Ir. Xitobe). 



Type in ]\Ir. Xitobe's collection. There are three other spe- 

 cies of this g'enns, each represented by only a single female, so 

 I have not described them. 



DiosTR()]\rBUs Tiller. 



(1) D. poUfus Uhler. 



I have both sexes from Formosa, but have not l)een able to 

 compare them with Japanese specimens. 



Male pygophor very short, nearly hidden by preceding segment, 

 anal segment long and narrow, reaching nearly to end of styles, apex 

 drawn out into an acute point, anus about middle, a small, blunt pro- 

 jection over anus. Styles long, spine-like, irregularly curved inward, 

 a small spine on inner side near apex, at base. The upper edge 

 produced into a large quadrate process with a small curved spine at 

 each upper corner. Aedeagus large, surrounded by the basal quad- 

 rate projection of styles. 



In the female the genital styles are very greatly reduced, but from 

 below them arises a pair of flattened processes, subparallel-sided till 

 near their pointed tips, each side of the preceding segment is pro- 

 duced into a nearly semi-circular plate; anal segment very short. 

 The female of this species is likely to be mistaken for the male on 

 account of these style-like projections. 



