ON A RATIONAL NOMENCLATURE OF THE VEINS OF INSECTS, 

 ESPECIALLY THOSE OF LEPIDOPTERA. 



BY A. S. PACKARD, PROVIDENCE, R. I. 



Hitherto there has been an unfortu- 

 nate hick of uniformity in the nomencla- 

 ture of tlie veins of the wings, diflercnt 

 names having been applied to the veins 

 of diflerent orders. 



In his paper on the phylogeny and 

 ontogen\' of the veins of the wings of 

 Lepidoptera Spuler has, however, given 

 us a simple scheme and a numbering of 

 the veins which will, we think, apply 

 in general to the wings of insects of all 

 orders. 



Redtenbacher had previously pointed 

 out that "the geologically older 

 Orthoptera and Neuroptera have a 

 much richer and more complicated 

 venation than the Coleoptera, Lepi- 

 doj^tera, Hymenoptera and Diptera ; 

 thus among the Rhynchota, the oldest 

 forms, the Cicadidae and Fidgoridae 

 have a much greater nuinber of veins 

 than the Hemiptera. There is no 

 doubt but that the oldest insects were 

 provided with an excess of veins, that 

 on the other hand in the course of 

 development this superfluity has dis- 

 appeared b)' a process of reduction, 

 and in this way a simpler system of 

 venation has resulted. It is also to be 

 observed that the size of the wings has 



had a considerable influence on the 

 number of the veins, since small forms 

 almost without exception have fewer 

 veins than insects with large wings." 

 Redtenbacher also believes "that the 

 normal type of a differentiated wing 

 may be found in those insects whose 

 fore and hind wings are most similar in 

 size and shape," and states that the 

 venation is not useful as an ordinal 

 character, but is of more service in 

 separating suborders and families. 



We agree with Spuler in rejecting 

 Redtenbacher's system, which is partly 

 based on Adolph's untenable theory of 

 convex and concave veins, but more 

 especially for the reason that Redten- 

 bacher assumes that the primitive 

 form of venation is that of the Ephe- 

 meridae. He remarks: "There is 

 scarcely another group of insects whose 

 wings show the primitive type, the 

 fan-shaped form, as the May-flies." It 

 may be objected to this that the 

 Ephemeridae, though in most respects 

 generalized and primitive insects, y-et 

 are, as regards the wings, highly 

 modified or specialized. That this is 

 the case is also suggested by the reduc- 

 tion or atrophy of the mouth-parts. 



