THE WING-VENATION OF THE COLEOPTERA.* 



Wm. T. M. Forbes, 

 Ithaca, N. Y. 



In the course of the last two generations, since the first 

 attempts by Adolph (Nova Acta der Leop. -Carol, deutschen 

 Akad. d. Naturf. 41(2), 213, 1880.) and Redtenbacher (Ann. 

 d. k. k. naturhist. Hofmuseums I, 153, 1886) the comparative 

 study of the wing- veins of the various groups of insects, sup- 

 plemented by that of their larval trachea, has shown that all 

 insect wings have a venation based on a common plan, whose 

 modifications in the various orders are for the most part, well 

 understood. In the Coleoptera, alone, of the larger orders, 

 there is nothing approaching agreement in interpretation, for 

 several reasons. In the first place the venation is sufficiently 

 unique, and complicated, to make such a superficial study as 

 brought even Adolph and Redtenbacher close to the truth in 

 the Lepidoptera, for instance, almost completely futile. The 

 complicated foldings also interrupt the veins and cause dis- 

 tortions in their courses. Further, the first forms studied for 

 their pupal tracheation were specialized Cerambycid^, a fam- 

 ily in which the tracheation is degenerate and no longer fully 

 corresponds to the veins. Several workers, notably Kempers 

 (Tijd. voor Entom. 42 to 45) and Kolbe (Archiv fur Naturges. 

 67: Beiheft 89, 1901) have been thrown off by Adolph's or 

 Woodworth's theories of an alternate system of convex and 

 concave veins, which in the manner applied by them, is decep- 

 tive in the higher orders. More recently d'Orchymont has 

 proposed a more carefully studied scheme, but his also ignores 

 the evidence of the tracheation, and to me seems only half 

 correct. Kiihne's study of the tracheation (Zeits. wiss. Zool. 

 112: 692) alone has resulted in essentially the same conclusions 

 which are expanded below. His paper is somewhat diagram- 

 matically illustrated and appears to have been largely ignored 

 by other workers; but I have veritfied his main conclusions, 

 the differences between our results being mainly a matter of 

 interpretation. 



* The expense of publishing this paper was borne by a grant from the 

 Hecksher Foundation for the Advancement of Research, established by August 

 Hecksher, at Cornell University. 



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