Ill STUDIES IN THE LONGICORNIA OF NORTH 



AMERICA. 



On rearranging the Cerambycids of my collection, it is noted that 

 the major part of nearly all the larger genera is composed of material 

 thrown together without sufficiently detailed study as a rule. An 

 attempt is made in the following pages to separate the various units 

 and subunits more carefully and on closer lines, in order to better 

 portray what the evolutionary forces have so far accomplished. 

 Some groups such as Prionus and Tylosis appear to be in a more 

 plastic condition than others at the present time, including forms 

 which though specific or subspecific according to criteria derivable 

 from general comparative studies in the Coleoptera, are so connected 

 by what might be interpreted to be intermediates, or depart so 

 little from the common model, that it seems correct to assume them 

 to be less well established than others and destined to speedy extinc- 

 tion in the struggle for existence; but it seems desirable to define 

 these less accentuated forms as well as the others, in order to record 

 what really exists at the present epoch of the earth's history. It is 

 only by carefully recording such data that certain phases at least 

 of the processes or laws of evolution can be finally deduced. It is 

 quite possible that some species already described and recorded 

 in our lists in this and other families, such as uniques remaining 

 such for more than half a century for example, of which we can 

 recall a number, are transitory forms of this kind that have appeared 

 in comparatively few individuals and soon crowded out of existence 

 by reason of changed environment or other uncongenial conditions. 

 I think however that all the forms to which names are here attached, 

 will prove to be at least subspecific and therefore worthy of definition 

 and formal record.* 



* All the species herein described as new inhabit the continent of North America, 

 excepting Zalophia spissicornis and Cyllene andesiana, which form part of the fauna 

 of Ecuador. 



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