V 
Preface. 
With the present 13 th volume, being the second volume of the Exotic Part, which I herewith place 
before the public, the Ethiopian Rhopalocera have been brought to a conclusion. For this division of the 
Macrolepidoptera of the World, the editor had succeeded in procuring the services of Mr. Christoph Aurivillius, 
of Stockholm, an authority on African lepidoptera, whose treatises and lists of Ethiopian lepidoptera have been 
universally acknowledged as a classical special work, in spite of their author’s great comprehensiveness. The 
first really comprehensive classification of African Rhopalocera, which was edited in the Swenska Vetenskaps 
Akademiens Handlingar, and then found a world-wide propagation as an independent list, has here not 
only been circumstantiated and supplemented, but it has also been augmented by an elaboration of the Ethiopian 
Grypocera. 
Thus the 13 th volume has the advantage over the others of exhibiting greater uniformity and homo¬ 
geneousness in the disposition, although by distributing the different families among several authors the volume 
might have been brought earlier to a close. When the programme of the whole work had been drawn up, nobody 
could foresee that the temporal events would put a ten years’ stop to the continuation of the work. It took brat 
a few years to elaborate this volume, as apart from a few sheets at the beginning, it was chiefly composed in 
the years 1911—-13, and then again in 1923 and 1924. The fact that the work on this volume was interrupted 
by the war and the first post-war years, was a natural effect of the intercourse of the country of origin with 
the foreign countries having been interrupted by the insecure state of Europe. If the long duration of these 
troubles could have been foreseen, the elaboration of this volume might have been contracted and abridged. 
But now, as these obstacles have been overcome, those using the work will be grateful for its being without 
a gap, and not so cursory as it would have certainly been if the author had endeavoured to bring it to 
an earlier close. The user of this volume will be particularly thankful for the insertion of tables of identification 
having been elaborated by the author for all the difficult lepidopteral groups, whereby the use and orientation 
have been greatly facilitated. They are of particular value, since the Ethiopian fauna which, unlike the other 
faunae, could only be explored in the last epochs, is confronted by considerable difficulties with respect to 
the identification. Owing to the excessive variability of African lepidopteral forms and to the facidty of their 
species to appear in frecpiently entirely dissimilar forms -— as for instance the Teracolus, Papilio dardanus, 
Hypolimnas dubia etc. — which we do not find in the same intensity neither from the American nor palaearctic 
regions, this great help in identifying the species, in addition to a key for smaller lepidoptera, such as Lycaenidae 
etc., was particularly welcome. This classification, however, was also connected with great difficulties, since 
there exists, up to this day, but very little material of a great many species having been recently discovered. 
The figures ■— almost 3000 — illustrating the text will presumalby suffice for the speedy information 
about the essential characteristics both of the principal forms, the groups of species and the total fauna. Consi¬ 
dering the very low price of the serial numbers sold at pre-war times, nobody will expect to see works of art 
which had never been promised nor intended, since such endeavours would have necessarily not only affected 
the price but also checked the progress of the work to a very great extent. Nor will the almost 1500 plates 
of the total work (800 of which have already been published) be claimed to be all of the same perfection. 
The publisher has spared neither expense nor pains in his endeavour of attaining a high finish, and also the 
editor believes to have done his best for their furtherance; but the most disadvantageous restriction of the 
import of raw materials during and after the war, being almost catastrophal to the dye-works, impaired the 
application of first-rate colours in the production of life-like coloured plates in Germany. Still greater difficulties 
arose from the recruiting of all skilled labour for the defence of the coimtry, as well as from the troubles during 
and after the Revolution, the detrimental effects of which have as yet not been entirely got over. Nevertheless 
the unprejudiced critic will find out that, after an unmistakable decrease of artistic performances in the years 
1920 and 21, during which time some plates of Lycaenidae were produced, a revival is distinctly noticeable 
