225 
IV. TROPIDUCHIDAE. 
Tropiduchidae Stal (1866), Hem. Afr., IV, p. 130; type Tropiduchus 
Stal (1854), Afr. Vet. Ak. Forh., p. 248. 
This family was monographed by Melichar in 1914, at which 
date he recognized sixty-nine genera. Since then several new 
ones have been added. 
With few exceptions the claval vein reaches to the apex of 
the clavus, which is acutely closed. In a few cases it joins the 
suture near its apex, and in a few it joins the claval margin 
near the apex. In many genera there is a distinct costal area 
with cross-veins; in others the costal area is entirely missing. 
The genus Alcestis is of interest on account of its peculiar vena- 
tion. What Melichar considers the subcosta I consider to be the 
costa, so that in some species there is a very small costal area; 
Sc and R are joined for some distance at their bases, and Sc 
gives out branched veins which reach the costal margin. 
Melichar uses the presence of a suture that divides the pos- 
terior angle of the mesothorax from the disc as the distinguish- 
ing character of the family. If the forms it brings together can 
be retained in one family, then it is of great service and relieves 
systematists of considerable trouble. 
We know little about the genitalia at present. The ovipositor 
appears always to be of the incomplete form. The aedeagus 
shows considerable variation in the different groups. In Ommat- 
issus loufouensis Muir (fig. 11) the periandrium forms a small 
ring with two long, slender processes; the penis is long, slender, 
tubular and slightly sinuate; the genital styles are separate. In 
Tabinia formosa (fig. 27) the genital styles are connected to- 
gether at their base, the periandrium is like a semitube on the 
dorsal aspect of the penis (an epiandrium), and the penis is 
tubular. In l’anua poyeri Muir (fig. 20) the genital styles are 
amalgamated together and form a single, asymmetrical organ; 
the periandrium is a long, slender, chitinous tube, and the penis 
is complex and large. There is a large apodeme connecting the 
base of the periandrium with the apodemes of the genital style. 
It is possible that what I term the periandrium in this genus is, 
in reality, the penis, and that the periandrium is absent. It 
recalls the type found in Derbidae, but it is curved in an oppo- 
site direction and there is an apodeme. It is necessary to do 
