266 
LIBETHRA; BOROCERA. By Dr. C. Aurivillits. 
straminea. 
jejuna. 
brunnea. 
-punctillata. 
cajani. 
margin red-brown, at the hind-margin light grey without markings. Fringes short, unicoloured, brownish-red. 
Wings beneath reddish-grey without markings. This little Gonometina occurs in the collections as . .Lasiocarnpa 
parvinota MabB (in litt.), but it is probably the $ of N. solida. — The £ (37 e) is much larger and chiefly 
differs from the $ of N. serratilinea only in the large silvery white discal spot surrounded by dark brown in 
the forewing. Madagascar. 
N. straminea Auriv. (— eborea Tams). Structurally very similar to the two preceding species and 
certainly better ranged here than in any other genus known. <$. Shape of wings and of body exactly as in the 
other <$<$. Unicoloured white with a black eye-circle; forewing above feebly yellowish, beneath in the discal 
cell and at the costal margin scaled blackish. Antennae black with yellow pectinations. Expanse of wings: 
36 to 40 mm. — $ larger, about 50 mm, otherwise similar to the A, but with darker tarsi and anterior tibiae. 
This peculiar species being separated from all the other Gonometinae by the colouring and marking was discovered 
by Henry E. Irving near Bloemfontein in the Orange Free State. 
14. Genus; Xdbethra Saalm. 
This genus is very closely allied to the following Borocera Bsd. and merely differs in the eyes being 
distinctly hairy also in the $$, and the hindwing showing a uniformly bent distal margin. As Saalmuller, 
in establishing his genus Libethra, had no specimens of Borocera cajani at hand, L. jejuna must be regarded 
as the type of the genus. If, as is asserted now, the shape of the A hindwing may vary in the same species 
(of course not only in hybrids), the most essential difference becomes untenable, and Libethra must then 
certainly be united with Borocera. 
L. jejuna Saalm. d (37 e) need not be described more accurately. The $ is unknown. Madagascar. — 
brunnea Saalm. d (37 e) only differs in the somewhat darker ground-colour and the absence of the subbasal 
transverse band of the fore wing. $ not surely known. Madagascar. 
L. punctillata Saalm. (37 e). d- Also here it suffices to refer to the figure. 0 unknown. Madagascar. 
L. cajani Vins. ( = bibindandy Camb.) d- Distal margin of hindwing rounded. Forewing above 
varying between red-brown and reddish grey with the usual three transverse lines and a discal dot being darker; 
the first transverse line is often indistinct or absent, the second fine red-brown, the submarginal line formed of 
smaller or larger grey or blackish scaled spots. Expanse of wings: 42 mm. — $. Much larger, about 72 mm, 
very light whitish-grey or ash-grey; the subbasal transverse line is distinct and angular, the discal line dark 
brown, the submarginal line composed of grey, distally open bows or irregular spots; discal dot brown. Hindwing 
unicoloured. — This species as well as some species of Borocera are used by the inhabitants of Madagascar for 
the production of silks. The larva lives on a Leguminosa (Cytisus cajan L.). A reliable description of it, however, 
is unknown to me. Cf. however Borocera madagascariensis\ 
15. Genus: ISoroeera Bsd. 
Palpi short, not or hardly projecting beyond the frons, with appressed scales in the A, somewhat bristly 
hairs in the $; last joint small, knob-shaped. Antennae of S the basal half with long, then shorter 
pectinations, in the $ with very short pectinations. Forewing of S long, narrow and pointed, of $ broader 
and less pointed; veins 4 and 5 rise near each other; 6 and 7 forked, 8 from the stalk of 6 and 7, 9 and 10 
on a longer or shorter stalk, 9 into the apex. Hindwing of '■ costal margin bent at the base, then often straight, 
apex sharp, distal margin straight or even somewhat concave (between the apex and vein 2 or 3); in the $ 
the costal margin is feebly bent and the distal margin uniformly rounded; vein 3 free and veins 4 and 5 on 
a short stalk from the posterior angle of the discal cell; the basal cell has 2 (or 3) distinct accessory veins 
and is closed by a moderately long cross-vein. 
The larvae are armed with sharp black needles which, however, are not scattered over the whole body 
as in the larvae of Gonometa, but they occur almost only on the decorative spots of the second and third segments; 
The cocoon is elliptic and everywhere armed with the sharp larval needles. All of them must be removed before 
the cocoons are utilized. 
It is a very remarkable fact that no life-like figures of the larvae exist so far nor any systematically 
or scientifically serviceable treatise on this interesting genus. Tire SS seem to be very variable and, for the 
present, we cannot say whether they are different species, races, or their hybrids, and it is still more impossible 
to decide which belong to the AS- Nor are hardly any figures serviceable, because they are finished 
in a too inaccurate or careless way. 
