180 ©. R. Osten Sacken: 
of this genus (see Westwood 1. c. and v. d. Wulp Tijdskr. XXI, 
p. 196) the following remarks will not be out of place. 
Libnotes agrees in all the primary characters with no 
(sensu stricto): antennae 14-jointed, the last-joint with an elongation 
sometimes simulating a 15h joint; structure of rostrum and lips 
similar to that in Limnobia; rather broad collare; genitals with the 
characteristic style on the underside; ungues dentate on the under- 
side; no spurs; no empodia; venation of the type of Limnobia, that 
is, a single submarginal cell; the end of the auxiliary vein far beyond 
the origin of the praefurca; four posterior cells etc. 
The peculiarity of this venation consists in an extraordinary 
elongation and curvature of the cells in the distal half of the wing, 
and in a corresponding shortness and obliquity of the praefurca; 
but these are characters of only secondary value, sufficient for the 
establishment of a genus, but not sufficient for involving a corre- 
sponding modification of the primary characters with it. Thus Lib- 
notes is nothing but a Limnobia with a venation, not modified at 
all in the groundplan, but strongly exaggerated in its details, which 
gives the insect a peculiar and somewhat deceptive aspect. 
Another peculiarity of Libnotes consists in the form and posi- 
tion of the stigma; it is shapeless, spread over the whole interval 
between the costa and the first vein, up to the tip of the auxiliary 
vein, but encroaching very little beyond the first vein; (usually among 
the Tipulidae brevipalpi, the stigma is cut in two by the first 
vein). L. familiaris alone has a small, rounded stigmatie spot at 
the end of the first vein. 
The venation, in its details, shows slight differences in different 
species. The bases of the 24 and 34 posterior cells are sometimes 
nearly on the same line (simplex, aurantiaca, T’hwaitesiana, inno- 
tabilis, impressa, Semperi, termitina); sometimes the proximal end 
of the 24 p. c. is nearer the root of the wing than that of the 34; 
(poeciloptera, notata, strigivena, imponens; quadrifurca and fa- 
miliaris hold the middle between the two forms). The relative posi- 
tion of the end of the first vein and of the marginal crossvein also 
varies in different species. In L. T’hwaitesiana the tip of the first 
vein is represented as incurved towards the second, the crossvein 
(not visible in the figure), probably being between it and the costa, 
The same structure exists in L. simplex, innotabilis, impressa, 
termitina, Semperi. In the other species, the first vein takes the 
usual course, the crossvein being more or less near its tip (at 
the tip in notata, strigivena and familiaris; not far from it in 
