902 
NOTODONTIDAE; GENERAL TOPICS. By Dr. A. Seitz. 
Of the 2300 species known the greatest number occur in America, i. e. about 1400 species. The palae- 
arctic region hardly harbours one tenth of the entire number of species known; the Ethiopian region hardly 
one sixth, and the Indo-Australian region about one fifth of the whole number. This vast legion of Notodontidae, 
however, is very unequally distributed in America. Most of them occur in the tropics wdiicli — as we stated 
in Vol. X — scarcely excel the temperate northern region on the eastern hemisphere in the number of species; 
in Asia — especially in the east — we may even meet more Notodontidae in the warmer countries of the 
palaearctic region, than in the plains of Tropical India; in America, on the contrary, the species prevail in 
the trojiical countries. 
The peculiar habit of most of the Notodontidae living on trees, is of the greatest influence on the 
distribution of the family in certain regions. The fact that certain districts, also of America, may be entirely 
devoid of trees, prevents the Notodontidae from penetrating to these parts of the country. In Egypt, where 
many districts even lack the scanty Nile-Acacia, so that there are no trees whatever to be found, except palms 
and wood-plants introduced from foreign countries, it is useless to search for any Notodontidae-, only in 
mountainous North Africa, where wooded valleys occur, do we meet Cerura, Pygciera, Hoplitis etc. Similar 
regions are found in America, where with an east wind continually blowing the Cordilleras, on their dry side, 
allow no moisture to fall. The saltpetre district of Iquique where it never rains at all is a good example. Nor 
could any Notodontidae develop in isolated districts of Mexico where there is no timber, and in the southernmost, 
open country of Chile and Patagonia where the unceasing, roaring wind that tears every tiny plant up by the 
roots or covers it with sand the moment it appears, the same situation prevails, for no woody plants can thrive; 
so the Notodoyitidae as well as most of the other Heterocera families are conspicuous for their absence. 
On the contrary, the number of Notodontidae known in the tropical, rainy, wooded districts of America 
is enormous and increasing continually. The number of (about 30) species newly described in this chapter 
points to a further increase. The boreal parts of America to the north of Mexico, however, are not much 
favoured; only 80 species being known from there up to now. The distribution of the family in Mexico itself 
exhibits the very same fluctuations in the different districts as the timber does. 
The concentration of some genera in particular districts is also obviously connected with the vegetation. 
The fact that some genera are confined to quite definite districts is also distinctly due to the vegetation. Thus 
w r e meet an amassment of species of the genus Schizura in the northeastern parts of the U. S. A., between 
Portland and Philadelphia, where 6 of the 8 nearctic Schizura are found, whereas Packard could identify there 
scarcely half of the North-American Datana which are widely distributed over the whole continent; the species 
of the genus Ichthyura (Melalopha ) are accumulated in Colorado, near the Springs and in Denver. We must, 
however, consider that some of these results are to be attributed less to a really abundant occurrence than to 
the fact that some very zealous collectors were at work in certain districts, who succeeded in tracing the rarer 
species as well. 
From Mexico, from where about 180 species are known, down to the northern parts of South America, 
the number of known Notodontidae increases to such an extent that the number of species yielded by collectors 
from one single town of Brazil sometimes doubly and even trebly exceeds those found in the U. S. A. In 
favourable weather, tw r o or three dozen Notodontid species are often captured on the lanterns of Rio de 
Janeiro or on the large arc-lamps which have been introduced of late even in the remote towns of Central 
Brazil. A great many members of this lepidopteral family come to the light from afar, and most of them remain 
fascinated by it, and are unable to leave, whereas Geometrids and, above all, Noctuids are rather frequently 
able to leave the flame again after having flown around it for a short time. 
There is hardly any other way of collecting Notodontidae in the tropics but by capturing them at the 
light. In the temperate zone, where access to the foliage of the trees is easy, most of the members of this 
family found in collections had been bred from larvae. The success of this method of collecting, however, is 
not very great. Breeding American species may be just as easy and safe as breeding European species, but 
the larvae are more difficult to capture when unfamiliar with their habits. Some are polyphagous, but many, 
as also some Europeans ( Ptilophora plumigera, Notod. dromedarius etc.) entirely or almost exclusively depend 
on a single food-plant. Others again are confined to a single family of plants, as for instance the Ichthyura 
on Salicaceae; whilst others live only on trees, though they attack lofty-growing wood-plants of various 
families. Thus breeding is rather difficult owing to this limitation to one or few species of food-plants, since, 
even if the name and appearance of the plant be well known, it is sometimes very hard to discover an easily 
accessible specimen for feeding the larvae. And even if the food-tree has been found close at hand, it is some¬ 
times only with great difficulty that fresh twigs can be fetched down from such a height, so that it is then 
more advisable to shoot fresh branches down with a rifle. In this case, however, another drawback has to be 
considered, i. e. that freshly broken twigs dry up very quickly, so that the transport from the often distant 
spot, where the food-plant grows, to the breeding-place of the larvae mostly results in very insufficient sap 
for feeding them. — It is hardly possible to-day to estimate the geological age from the feeding-conditions, 
