1001 



on both wing-sides, though most frequently on the under side. la a 

 general survey of the wlng-niarkings of Lepidoptera, wiiich I under- 

 took long before Botke's doctor-dissertation, and wrote in Englisii, 

 but wliicli I did not hitlierto publish, I even thought it desirable 

 to choose a special nauie for this curious motive of design and 

 called it "Cosside markings". 



Now it might very well be, that these markings could also be 

 reduced to an old and original motive of design, occurring genei-allj 

 among insects, and whose connection with the system of internervu- 

 ral spots still wants elucidating, although Botke has made a notable 

 attempt to come lo a general theory. 



That a "sympathetic" design, on account of its mimetic chaiacter, 

 should necessarily be younger than other patterns, I deny most 

 emphatically. Each of the elements, which by their coö|)eration 

 produce the mimelic etïect, may in itself depend on hei-edilary 

 tendencies of very high phylogenetic antiquity. Only the specific 

 and special culmination of that cooperation may be young, and 

 even this need not necessarily be the case. Among Pieiids, Papilio- 

 nids and Nymphalids the mimicrists probably often wear a?i older 

 and more primitive uniform than the remaining so-called typical 

 members of these families, as 1 have tried to demonstrate in my 

 paper read at the International Entomological Congress at Oxford 

 in 1912. 



In numerous Geometrids, issuing from their pupae in autumn, 

 the similarity to a weathered leaf reposes on their light-yellow 

 colour, besides on the broken rim of their wings and the course 

 and arrangement of dark transverse lines on them, imitating the 

 veins of the leaf. Must on this ground the yellow hue be younger 

 than other tints? According to my view this need no more be the 

 ease than it need be assumed for the form of the wing-border or 

 the pattern on its surface, even when granting that in general a 

 broken border-line has to be derived from an unbroken, round- 

 ed one. 



In the same way the evident connection between spots, stripes 

 and meshes on the wings of Cossids, which can so to say be read on 

 the wing-surface by simple observation and by comparison with the 

 Zeuzerids, is in no way brought nearer to an explanation by the 

 reniark, that the preponderance of the net-markings produces a sym- 

 pathetic resemblance to the bark of trees. The real question remains : 

 what causes tendency of the Cossid wing-markings to the net-character 

 and how old is that tendency ? In putting this question we have to 

 keep in view, that the same tendency occurs in many other insects 



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