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Thoroughness in Entomological Tables. 

 By T. L. Casey. 



Analysis should invariably precede synthesis and generalization. Ap- 

 plying this truism to the science of Entomology, we readily perceive that 

 . it may be considered from two points of view — the purely scientific and 

 the practical. Concerning the former it is intended to refer to the 

 necessity for a minute knowledge of all the parts before the whole, or the 

 mutual relationship of the different parts of the whole, can be properly 

 understood. Regarding the latter, or the practical application of the 

 principle, it is desirable to indicate the great inconvenience and loss of 

 time infiicted upon our students by the present method of simplification 

 or synthesis as exhibited in tabular statements of genera and species. 



In order to illustrate our meaning more clearly it is only just to cite 

 some one of the multitude of examples continually occuring. In this il- 

 lustration it is necessary to refer to our only work on a systematic arrange- 

 ment of the North American genera of Coleoptera, a work the inestimable 

 value of which it is not intended in the least to overlook or underestimate; 

 in other words it is not meant in the spirit of captious criticism, but 

 simply as a random example of the practical efitbrts of this so-called 

 simplification. 



Let us asume that the student holds in his hands a s{)ecimen of 

 Badisfcr, which is entirely unknown to him and the generic identification 

 of which he is desirous of obtaining. The tables given in this work carry 

 him easily to the second part of the scheme given on page 21, or to those 

 genera without elytral fold. Here he is at once met by a difficulty. The 

 first character to be consulted is that of the front, whether short or nor- 

 mal, which being of no positive value unless he is familiar with the entire 

 series, we will not consider, but pass to the next character which is that 

 of labral structure. If this organ is impressed the insect is to be referred 

 to the Licinini, if not, he should naturally search further. Examining the 

 laljrum of Bac/is/cr it is found to be deeply and narrowlv emarginate or 

 cleft to the very base, leaving no space whatever for an impression, he 

 therefore continues his quest for applicable characters, and it is only after 

 reading the lengthy diagnoses of many other groups, that he arrives at the 

 conclusion from purely negative evidence that his species must be included 

 in the Z/'cih/m. If there had been less simplicity and concentration fol- 

 lowed in the scheme, and if the group Badisferini had been there correct- 

 ly indicated, it is true that the tables would have been longer and more 

 complex, but much valuable time and vexation of spirit would have been 



