216 ©. R. Osten Sacken: 
My statements in the Monographs were based on descriptions 
only; I was uncertain whether Polymera belonged to the Limno- 
philina or perhaps to the Amalopina. Since then Loew had an 
opportunity to examine well-preserved specimens and has settled the 
question in favor of the Limnophilina. (Loew, Zeitschr. f. d. ges. 
Naturw. Vol. XXXVI, 1871, p. 2535—267.) He showed at the same 
time that the antennae are only apparently 28-jointed, but in reality 
have the normal number of 16 joints; the joints of the flagellum have 
each two knots or swellings which are easily mistaken for separate 
joints. The open discal cell and its coalescence with the third 
posterior cell, are exceptional characters among the Limnophilina 
(compare O. S., 1. ec. IV, p. 191). The known species are South 
American. 
Phyllolabis. 
O. Sacken, Western Diptera, p. 202—204; 1877. 
Belongs to the Limnophilina with four posterior cells, and 
is remarkable for the unusual structure of the male forceps and the 
total absence of the marginal crossvein; its immediate relationship 
with the other genera of the group, for this reason, not being ap- 
parent. I reproduce the description from my above-quoted paper: 
Two submarginal cells; four posterior cells; discal cell closed; 
subcostal crossvein a very short distance before the tip of the auxi- 
liary vein, which is immediately before the stigma; no marginal 
crossvein; first submarginal cell about half as long as the second, its 
slightly arcuated petiole occupying the length of the other half; the 
second vein and both of its branches are pubescent; the other veins 
are somewhat pubescent before their ends; eyes glabrous; antennae 
16-jointed; tibiae with exceedingly small but distinct spurs at the tip; 
empodia small but distinct; ungues smooth. The abdominal segment 
bearing the genitals is unusually swollen in both sexes, bearing in 
the male a large forceps with horny appendages on the inner, and a 
long foliaceous whitish appendage on the under side. 
The stature and general appearance are those of a Limnophila. 
Antennae, when bent backward, nearly reach the root of the 
wings; the joints of the scapus have the usual structure; the flagellum 
is not perceptibly stouter at the base than at the end; the joints have 
that subeylindrical shape, attenuated at the point of insertion and 
vertieil-bearing about the middle, which is quite common among the 
Limnophilina; they gradually decrease in length toward the end 
and become more oval; verticils short; front moderately broad. 
Vertex but moderately convex. 
