ODONTOPACHA. By Dr. C. Aurivillius. 
0. nigricans Auriv. (35 a). <$. Blackish; forewing above with two strongly curved and slanting nigricans. 
transverse lines. Hindwing blackish, before the margin with traces of two dark transverse lines. Wings beneath 
sooty black. Expanse of wings: 42 mm. The $ is larger (66 to 70 mm), somewhat lighter, the transverse lines 
of the forewing more broadly separated. Patagia black. Thorax dark grey. Gold Coast and in the Sesse Islands 
in L. Victoria Nyanza. 
27. Genus : Otl on to pacha Auriv. 
Palpi long, porrect, projecting far beyond the frons; last joint horizontal. Eyes hairy. Tarsi at least 
at the base hairy. Distal margin of forewing behind the sharp apex emarginated, and at the end of vein 5 or 4 
angular, hindwing uniformly rounded. Forewing: veins 4 and 5 rise separately from the posterior angle, 8 from 
the long pedicle of 6 and 7, 9 and 10 as long as, or longer than their pedicle, 9 into the costal margin. Hindwing 
with an almost straight costal margin, vein 3 from the posterior angle of the cell or from the long pedicle of 
the veins 4 and 5. Basal cell small. In the very closely allied East-Indian genus Bharetta Moore (cf. 
Vol. X, p. 401, pi. 35 c) the distal margin of the forewing is angular at vein 6, and the accessory vein of the 
basal cell of the hindwing is much longer. 
0. fenestrata Auriv. (35 c). Body and bases of both wings light fawn-coloured. Wings otherwise fenestrata. 
with a greyish ground-colour. Eorewing at the costal margin near the apex with a red-brown spot; its transverse 
lines are single, almost smooth, at the anal margin curved towards the base; submarginal line whitish, near 
the apex with small hyaline spots. Hindwing with two dark transverse bands. East Africa: Lindi. 
0. kilwana Strd. (40 a) has almost the same shape of the wings as fenestrata, but as the figure shows, kilwana. 
cpiite a different marking, the transverse lines of the forewing being upright and almost straight, and the sub¬ 
marginal line being absent. Hindwing only with a dark transverse band which is still more distinct beneath. 
East Africa: Kilwa. Rhodesia. 
7. Subordinate Family: Gonometinae. 
This subordinate family is distinguished by the size and formation of the basal cell of the hindwing. 
It is just as broad as, or broader than the discal cell and as long as, or longer than the anterior margin of 
the discal cell (from the base to the anterior angle), but not always projecting so far as the posterior angle 
of the discal cell. It is always formed by the veins 7 and 8 being united by an almost invariably long and 
slanting cross-vein. If we do not consider this mark, it is cpiite impossible to determine correctly the genus 
of a Lasiocampid. The formation is also very easily visible, if one scales off a little the base of the hindwing 
beneath or moistens it with toluol or xylol, whereby the clothing becomes sufficiently transparent so as to be 
able to observe distinctly the veins. 
The neuration is otherwise so different in the genera that they have only two marks in common: veins 
4 and 5 of fore wing are never forked, and the discal cell is in both wings closed. 
The Gonometinae are better represented in the Ethiopian Region than in the other regions, since no 
less than 26 genera with about 128 species occur there. From the palearctic region the genera Anadiasa , Cosrno- 
triche, Dipluriella, and Selenepliera are known, and from the Indo-Australian only Cosmotriche and Lenodora. 
The genera are partly very closely allied with each other, so that it is difficult so separate them distinctly. 
The following table is therefore only to be regarded as a provisional one. 
Table of Genera. 
I. The distal margin of the forewing forms a distinct angle at the end of vein 5. Vein 9 of forewing into the 
apex or costal margin. 
*. Vein 8 of forewing from the discal cell. The pedicle of the veins 9 and 10 is much shorter than the 
veins. — <$. Distal margin of hindwing rounded. 1 . Gonobombyx. 
**. Vein 8 of fore wing from the pedicle of 6 and 7. The pedicle of the veins 9 and 10 of the fore wing is 
not or hardly shorter than the veins. — Distal margin of hind wing deeply emarginated. 
2. Gonopacha. 
II. Distal margin of forewing uniformly curved, entire or feebly undulating, rarely somewhat irregularly curved, 
but not angular at vein 5. 
A. Palpi short, not or little projecting beyond the frons, rarely somewhat longer, but at most twice as 
long as the head. 
a. Anal margin of forewing only moderately hairy without long scale-hairs. 
