36 Annals of the South African Museum. 



than their width at the base ; the sides outside them closely serrate, 

 between the edge is rough. Basal abscissa of radius half the length 

 of the second ; as long as the transverse cubital nervures. 



This species may be known from what I make out to be the wide- 

 ranging G. furcata, Gu^r., as follows : — 



Abdomen immaculate, the apical teeth long, half the length 

 of the space between them, basal abscissa of radius one-third 

 of the length of the second, shorter than the transverse cubital 

 nervure ; the apex of abdomen not much more strongly 



punctured than the base ftn\-at(i, Guer. 



Abdomen with a large, bifurcated black mark ; its apical 

 teeth short, about one-fourth of the length of the space 

 between, basal abscissa of radius nearly one-half of the length 

 of the second and not much shorter than the transverse 

 cubital ; the apex of the abdomen much more strongly 

 punctured-reticulated than the base bilolxitd, Cum. 



ESENGA, gen. nov. 



Abdomen with six visible segments ; the second very large — as 

 large as the thorax ; the first about one-fourth of its length ; the 

 iipical small ; the first excavated at the base, its top surrounded by a 

 border. The third and fourth joints of antennae about equal in 

 length. Occiput not margined. Parapsidal furrows distinct ; the 

 middle lobe furrowed down the middle. Transverse median nervure 

 interstitial ; recurrent nervure received in the first cubital cellule ; 

 the second cubital cellule square, oblique ; the first abscissa of the 

 radius minute ; anal nervure almost interstitial ; second discoidal 

 cellule closed at the apex. Hypopygium projecting, cultriform ; 

 sheaths of ovipositor short. 



It is possible that the very large second abdominal segment may 

 represent in reality two, for, behind its middle, there is an indication 

 of a suture. 



The afi&nities of this genus are with Gastrotheca and Trigaslro- 

 iheca ; from both it may be known by the apex of the abdomen 

 being neither toothed nor lobate ; the latter has not the second seg- 

 ment larger than all the others united ; the first abscissa of the 

 radius is not minute and the anal nervure is not interstitial ; the like 

 difference in neuration separates it from Gastrotheca. 



* ESENGA OVATA, Sp. nOV. 



Luteous, the pleurae of a paler yellow colour, the antennae, front, 

 vertex, and occiput broadly black ; wings hyaline, the costa and 



