Zoology. — “The wing-design of Chaerocampinae’. By Prof. J. F. 
VAN BEMMELEN. 
(Communicated at the meeting of October 25, 1919). 
In a monograph, which is now being published as a supplement 
to Zeitschrift für Wissenschaftliche Insectenbiologie von Car. SCHRÖDER 
in Husum, and of which I received the first part a few months 
ago, Dr. P. Denso, the author of Palaearctic Sphingides in Skitz’ 
Macrolepidoptera, begins a description of the lepidopterous hybrids 
that have hitherto got known, with considerations on the wing- 
design of the species of Celerio. On page 1 he says about this: 
“Thorough investigations and theoretical considerations, which it 
would lead me too far astray to reconsider here, clearly show that the 
markings (and hues) of all Celerio-moths may easily and without 
constraint be derived from a primitive form, which only very 
slightly deviates from the pattern still found in the oldest species 
of Celerio, viz. zygophylli O., or likewise in lineata, when we only 
abstract from the white striation of the wing-veins. It must be 
mentioned here, that the original design of the species of Ce/erio is nearly 
related to that of the more closely-connected species of Pergesa”. 
I deplore that Denso did ‘not think fit to publish in detail his 
“thorough investigations and theoretical considerations” on the phy- 
logenetic interrelations between the different species of Celerio. 
For now we are obliged to deduce the grounds for his assertion 
“that zygophyll and lineata have to be considered as the (phylogene- 
tically) oldest species’ from a few remarks, which must be picked 
up here and there in the course of his paper. 
Such being the case, I prefer first to expose my Own views inde- 
pendently of Denso’s considerations and afterwards to discuss his 
deductions. 
In my eyes the only way to acquire a trustworthy insight into 
the wing-design of Celerio-species, is to compare it with that of 
other genera of Sphingids, especially Chaerocampinae. When keeping 
this course, it becomes evident that their colour-pattern is a highly 
modified variation of the general ground-design of Heterocera-wings, 
due to reduction and obliteration of the general primitive set of 
seven transverse bars, by the influence of the V-diagonal-motive 
(this being the name which in my foregoing paper on the wing- 
pattern of Saturnidae [ gave to the system of linear markings running 
