176 ©. R. Osten Sacken: 
All the described species belong to the tropical regions of South- 
America. 
I have seen in the Vienna Museum a Limnobia from South- 
America which combines the development of the proximal portion of 
the wing of Peripheroptera with an elongation and curvature of the 
‚apical veins somewhat approaching Libnotes, and I merely mention 
this in order to prove the variety of modifications of which the ori- 
ginal type of Limnobia is susceptible. 
1. P. nitens Schiner, R. der Novara, p. 47, Tab. 2,f.3, 52. 
— Colombia, S. Am. 
The auxiliary vein ends a little before the origin of the praefurca; 
subcostal cerossvein nearly opposite the middle of the first basal cell, 
very distinct, as in P. Schineri; first longitudinal vein incurved 
towards the second; the crossvein long before its tip, connecting it 
with the costa; praefurca very short, curved; proximal ends of the 
submarginal, first posterior and discal cells not in a line; distance 
from the root to the distal end of the triangular cell not much shorter 
than the first basal cell; the fifth and sixth veins anastomose near 
the stout crossvein. — These characters exist also in the female; 
but the thickening of the costa at and beyond the end of the first 
posterior cell does not exist here; the stigma is much smaller; the 
distance between the seventh vein and the posterior margin is a little 
broader in the male, but the difference is not very marked; ovipositor 
very small (Note taken from the types in Vienna). 
2. P. aberrans 2. 
Rhamphidia aberrans Schiner, Reise d, Novara ete. p. 43. 
South America. 
The triangular cell here is comparatively a little shorter; the 
praefurca a little longer and more straight; the proximal ends of the 
submarginal, first posterior and discal cells are in one line; the first 
longitudinal ends in the second, but the erossvein connecting it with 
the costa is nearer its end than in the preceding species; the course 
of the auxiliary vein and the position of the subcostal crossvein are 
the same. (Note taken from the type.) 
3. P.incommoda n. sp. &. Black, thorax shining; discal 
cell open; proximal end of the submarginal cell much before that 
of the first posterior. Long. corp. 4 mm. 
Head altogether black (brown in old specimens); antennae of 
the same color; front whitish, hoary. Thorax black, shining, hoary 
on the pleurae; abdomen, including genitals, brown; halteres yellow 
