JOURNAL 



OF 



THE ACADEMY OF NATURAL SCIENCES 



OF PHILADELPHIA 



ART. I. — An attempt to classify the Longicorn Coleoptera of the part of America 

 North of Mexico. By John L. LeConte, M. D. 



(Coiicluded from page 340.) 



Subdivision II. CERAMBYCIDJ]. 



Tiie same objections tiiat have been already made to Serville's arrangement of the 

 LepturidcB, may be urged with still greater force against his classification of this 

 subdivision, since the number of generic forms being very much larger, the 

 difficulties experienced in an artificial classification depending of superficial characters 

 become much increased. His primary subdivisions being formed on differences in 

 the outline of the thorax, the student is frequently left in doubt where a genus should 

 be placed ; and, indeed, if his system were rigidly followed, many species would be 

 separated from their congeners, and placed in a very different position from that 

 which nature indicated. Examples may be observed in the genera Elaphidion and 

 Arhopalus, as defined below. The affinities of this subdivision have been sufficiently 

 pointed out in the introduction ; it is the central group of the Longicornia connected 

 with all the others. Its affinities being of this radiating nature, we would naturally 

 expect to find it subdivided into a series of groups, each verging more or less in the 

 direction of one of these radiating lines. In a group thus constituted, the dichotomous 

 principle invariably adopted by the French naturalists fails completely, and we are 



VOL. II.— 2 



