III. — Coleopterological Notices. 

 V. 



BY THOS. L. CASEY. 

 Read Oct. 2, 1893. 



In bringing together a number of short studies of our North 

 American Coleoptera under the above title, the methods and objects 

 held in view in the other parts of the present series are continued. 

 The systematic revisions do not pretend to approach completeness, 

 and are merely efforts to indicate the probable interrelationships of 

 the species, based upon such material as it has been found possible 

 to gather together. New forms are continually being brought to 

 light, which sometimes tend to alter previously formed conceptions 

 of specific limits, or to destroy or modify the value of characters 

 assumed as the bases and criteria of classification. This is the 

 natural outcome of all endeavors to evolve the laws of complicated 

 affinities from inadequate data, but, at the same time, it is not 

 always necessary or advisable to defer the announcement of such 

 apparent truths as we have been able to discover with the material 

 at our disposal; if carefully conducted, I believe that they may, and 

 generally do, lead onward and upward. 



Having before us a confused mass of material which it is proposed 

 to classify and arrange generically and specifically, the problem is to 

 record all the genera and species, but neither more nor less. This 

 problem is frequently more difficult than any which can confront us 

 in the domain of the exact or physical sciences, because the acci- 

 dental and variable factors cannot be determined. We might illus- 

 trate the process by imagining an exact circle finely drawn on paper, 

 and then trying by free hand to retrace it with a blacker pencil. It 

 will be found that a portion of the dark line is outside the circle, a 

 portion within, and another truly on the line. The portion without 

 represents an excess of units or species, that within those which we 

 have overlooked, as shown by subsequent and fuller evidence. The 

 Annals N. Y. Acad. Sci., VII, Oct. 1893.— 19 



