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ART. XXVII.— An attempt to classify the Longicorn Coleoptera of the part of 
America North of Mexico. By John L. LeConte, M. D. 
Works cited. Hald., Haldeman in Transactions of the American Philosophical 
Society. Vol. X. 
Harris, Transactions of the Hartford Society of N. H. 
Say, Boston Journal and Journal of the Academy of Natural Sciences, 
Philadelphia. 
Nm. Ent. Mag., Newman in Entomological Magazine. 
F ORSTER, Centuria Insectorum. 
Dej. Cat., Catalogue de la collection de M. LeComte Dejean. 
Serville in Annales de la Societe Entomologique. 
Fabr., Fabricius. 
Ol., Olivier. 
Kb., N. G. Kirby Fauna Boreali Americanje. Vol. IV. 
Randall, Boston Journal of Natural History. 
Germ., Germar Insecta Nova. 
Lap., Laporte et Gory Monographic du genre Clytus. 
PART I. CONTAINING THE CERAMBYCI. 
f 
In the present essay I have made many innovations in the former arrangements of 
these insects. These will be found more obvious in the first group, the Lepturidae. 
The indistinct characters of the genera as left by Serville and Mulsant, have long 
rendered some other classification necessary ; since being founded on very slight and 
arbitary differences of form, they unite together many species which, agreeing in 
certain trivial circumstances, differ widely in general appearance. Such is the genus 
Pachyta, which on account of its heterogeneous nature I have been compelled to 
suppress altogether. Such again is Gmmmoptera, which was established on Lepturce 
with linear elytra. If a comparison of a large number of species be made, this 
character is found to be entirely fallacious, so that however clear the mathematical 
distinction may be between lines that are and are not parallel, it will be seen that in 
nature this distinction cannot obtain. The proportions and form of the elytra vary 
in all the genera, and it would be quite as rational to separate into distinct genera, 
those with incised and those with dehiscent elytra. 
Although these characters are thus shown to bo mere specific marks, we may • 
derive much aid from them in forming sections in those genera which contain many 
species; they may thus be made to alleviate the labor of identifying species: and in 
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