540 
MAC'ROCOSSUS. By M. Gaede. Introduction by Dr. A. Seitz. 
of nearly every great flood and sometimes transported down the rivers through whole continents. Whoever 
may chance to examine tropical trunks in search of borers and sees how the great number of drifting logs 
sometimes resembling a floating island are carried off, will realize how very easily the Cossiclae may be trans¬ 
ported in the most natural way. In such a way presumably has Zeuzera pyrina reached North America, where 
it now frequently occurs here and there, and a specimen of Cossus cossus was discovered in South Africa, 
probably having been imported in the timber. If the number of those Cossidae which are widely distributed 
in Europe were greater, the vast export of timber would probably influence the fauna of other countries to a 
higher degree. 
The total number of Cossidae known was stated by Kirby at the end of the last century to be 200 
species. But already when the second volume of the “Macrolepidoptera” appeared, about 130 forms could 
be counted occurring in the relatively poor palaearctic region, while Staudinger <b Rebel, in 1901, had only 
mentioned 85 species increasing to 100 in 1911. Today the total number of all the species known amounts to 
500, of which 85 species with more than 100 named forms occur in the Ethiopian Region. America abounds 
in Cossidae as in all the other lepidoptera, about 200 forms being known from that country, 21 of which occur 
in the nearctic district, the rest in the neotropical regions. 
The habits of the Cossidae are still hardly known, as their hidden existence makes it very difficult to 
explore them. We know only very few larvae of the palaearctic species and next to nothing about the larval 
life of the Ethiopian forms. Some species certainly live in the trunks of the large acacias and sycamores which 
are to be found as isolated trees dispersed over the Central African steppes; above all the Cossus itself, presum¬ 
ably also the species of Xyleutes. The smaller forms, such as the Arctiocossus and Holcoceroides, probably grow 
up in the trunks and roots of shrubs and grasses of the steppe, and the Phragmataecia in the stalks of reeds, 
as the palaearctic and Indian species of this homogeneous genus also do. If the reeds were used for industrial 
purposes in the Ethiopian regions, as in many places of Central Europe, the pupa of Phragmataecia would be 
just as easily obtained there as here, because the larva is in the habit of closing the hole, where it entered, with 
a silky web before it pupates, so that the inhabited reeds can be noticed from afar. Hitherto, however, we are 
still inexactly informed of the life of the Ethiopian Cossicl larvae, because our entire knowledge of the species 
of that district is founded almost exclusively on the capture of the imagines on the lantern. 
It has neither been possible to ascertain whether the Ethiopian Cossidae have a similarly long larval 
stage as their European allies. But as the tropical Indian and Australian Xyleutes are reported to have a larval 
stage of several years, it is hardly to be doubted that the larval life of the Ethiopian species is just as extensive; 
except that instead of the hibernating period of the European species a summer-pause takes place in Africa, 
which corresponds to the intensity of the dry period in that region. 
Much has already been told in Vol. II (p. 417) about the habits of the Cossidae and it was stated that, 
owing to the strong and parallelized neuration together with the very strong lamels of the wings, even large 
Cossus are enabled to extend the wings vertically upwards, when they sit on a horizontal surface (Frings). 
The wings stiffened in this way become very hard, so that the insects are able to fly very swiftly and con¬ 
tinuously. However, it is only the which swarm, for which reason also the $$ of many Cossid species are 
still unknown; sometimes even of species (such as South-American Hypopta) the <§<$ of which sometimes appear 
in such enormous numbers that they cover the ground even in towns. In contrast with this vast occurrence 
of single species there are only very few specimens known of many Ethiopian Cossidae , few of which are 
perfectly preserved, because of the damages caused by their impetuous flight and the frequent collisions with 
their hard wings. 
The proboscis is always absent. The palpi are feebly developed. Antennae of different kinds, rarely 
Bombycid-like long-combed to the tips, mostly only pectinate on % or % of their length in the male, in one 
genus only finely dentate. Hind tibiae with 1 or 2 pair of spurs of a variable length or without spurs. Fore wing 
with 2 inner-marginal veins and an accessory cell or an inserted cell. Hindwing with 3 inner-marginal veins. 
Vein 8 free next to the cell or connected with its apex by a cross-bar, besides fused in the middle with a bar 
in one genus, in another genus with vein 7. Both wings in the cell with a forked partition-vein. The larvae live 
in the interior of plants, except the two last genera. Distinguished from the family of the Arbelidae by the 2 
inner-marginal veins on the forewing and the invariably present frenulum, from the Limacodidae by the forked 
partition-vein of the discal cell. 
1. Genus; Maeroeossus Aur. 
Separated from the following genus Cossus by its considerable size. Antennae of as in the Lasio- 
campidae, strongly pectinate to the tips, in the $ somewhat less so. In the hindwing vein 8 is connected with 
the centre of the cell by an oblique vein, otherwise the neuration is the same as in Cossus. 
