84U 
SPHINGIDAE. General Topics. By Dr. A. Seitz 
about 250 Sphingid species known from America only 20 have succeeded in traversing this desert. We have 
stated at another place that because of their great want of food the Sphingidae being otherwise provided with 
such an excellent flying power are unable to fly across districts void of vegetation; they will not grow exhausted 
in such an attempt, but they will die of starvation. There is hardly any group of lepidoptera the imagines of 
which exhibit such a greed after food, and hence their communication between North and South America is 
most strongly obstructed. The fact that the entire American Sphingid fauna contains but 2 species occurring 
also in the Old World is due to another cause. In Vol. X we had stated that the Sphingidae chiefly belong to 
the more modern periods of creation, and that is evidently also the reason why the modern climatic conditions 
have been decisive for them. Their emigration from America to Western Europe, or from Eastern Siberia to 
Alaska might have taken place in such northern latitudes in which the arctic cold being unbearable for 
Sphingidae makes it impossible. Thus we do not find any single American Sphingid species in Eastern Asia, 
and only two species — these even rather widely distributed — in Europe and North America. Even very 
extraordinarily distributed lepidoptera, such as the Acherontia occurring from Lissabon to Japan and from the 
Cape of Good Hope to Central Europe have not been able to advance to America. The extremely problematic 
“Atlantis” — if it ever existed — certainly did not exist at the time when the Sphingidae spread over the world. 
The genera common to both the New and Old World are naturally those which are able to advance 
farthest to the north: i. e. the genus Smerinthus the Canadian form of which, S. cerisyi, is a continuation of the 
European S. ocellata extending to Lapland, Scotland, and England, and Sphecodina which extends in Eastern 
Asia to Siberia and which, though it does not occur any more in the nearctic west of America, is frequently 
met with again in the east in the winter-cold lake district. 
There are also other parallel features of these very homogeneous Sphingidae in the New and Old World. 
The exterior of the palaearctic Acherontia is opposed in America by the Grammodia. The American Protam- 
bulyx from the eurycles- and strigilis- group we find sitting in almost the same position on the large leaves of 
low shrubs in the open daylight as the Indian Oxambulyx. The palaearctic Macroglossa appear in America as 
Sesia and Eupyrrhoglossum, the South-Asiatic Panacra as Perigonia ; all these convergencies cannot be wonder¬ 
ed at considering such homogeneous habits, and they must not be used as a proof of systematic affinity. 
The differences between the various American Sphingid groups can only comprehensively serve as a 
key for a natural grouping; there is no organ exhibiting such thorough differences as to be able to build 
up a system of the Sphingidae on it; this also proves that the genera and species belonging to this family have 
been separated at a relatively late period, which assumption is substantiated by the great easiness of the copula 
not only between different species, but even different genera. These trials have almost become a sport, since 
new and often wonderful combinations are produced nearly every year. Nor do these hybrids by any means 
make the impression of stunted forms or unnatural deformities, but on the contrary they represent insects 
fully capable of living, and even the hybrids from mixed copulae of different genera bring forth prolific indi¬ 
viduals. Such hybrid larvae yielded by mixed copulae, as Denso already stated in Vol. II (p. 260 sq.), even 
prove to be of a particularly excellent appearance and to grow up very quickly. C. F. Fkings reports that 
hybrid larvae of liybr. johni Frings were already transformed to pupae after 16 days, thus in a space of time 
in which neither of the parental species (Smerinthus planus A and Amorpha populi $) use to terminate their 
larval stage. 
As most of the other lepidopteral families the American Sphingidae also exhibit a great abundance in 
gigantic forms. The species of the genus Cocytius with an expanse of almost 20 cm extend through the whole 
neotropical region and sometimes even advance to the United States. They represent, in a certain measure, 
our Acherontia which are absent in America and seem likewise to be subject to a continuous roving spirit, at 
least I frequently found the dead bodies of these lepidoptera on the Brazilian Coast, which had been deposited 
there by the tide. The Pachylia also develop very bulky bodies and their larvae may become so very heavy 
that the twings of young food-bushes are bent down by their weight, and this is still more remarkable in the 
Pholus anchemolus living on creeping plants. Dwarfish sizes of certain palaearctic species, such as Sphinge 
naepiopsis nanum or obscurus, do not occur in America. 
The colouring of the American Sphingidae does not differ typically from the palaearctic forms. The 
visible parts of the body are here likewise hidden by bark-like or leaf-like colouring or shades in most of the 
resting lepidoptera, the bright red or yellow colours are confined to the hindwings which are covered in the 
resting insect and the covered dorsum of the abdomen. The flying imago exhibiting the very bright colouring 
seems to be well protected by its swift flight and easily to notice an approaching enemy by the aid of its very 
large night-eyes and a certain shyness, even when sucking from blossoms, can be noticed as long as the 
dawn-time which is very short in the tropical districts allows our eyes to watch the insect. 
