xiv BIOGRAPHICAL SKETCH. 



'J'hree years iigo, " when he realized that his heaUh was failing, he ex- 

 pressed the desire," writes Dr. Horn, in his own modest account of their 

 common task, " that I should join him in more active authorship in the 

 work'" which was to contain the final results of more than thirty years' 

 systematic study of the Coleoptera of North America. '' The first pages 

 went to press in January, 1882, and the book was completed in March, 

 [lSS:i] ill time for him to realize that it had been at least well received. 

 For obvious reasons," continues Dr. Horn, " I cannot dwell upon the 

 merits even of his share of this work, except to say that his earlier edi- 

 tion is the basis of the prcvsent ; without the former, the latter might not 

 have appeared. Evidences of his influence will be found on every page, 

 and whatever it was my privilege to contribute was made possible entirely 

 by his early instruction and guidance." 



A comparison of the early and the later work, separated by an interval 

 of over twenty years, is most instructive. The classification of Coleoptera 

 proposed by Olivier, founded primarily upon the supposed number of 

 tarsal joints in the front and hind legs, was long so firmly established in 

 entomological tradition, especially from the support given it by Latreille 

 in his numerous general works, that it held some sway long after it was 

 proved to be artificial. It served a useful purpose, however, in showing 

 that this great assemblage of animals, of which more than a hundred 

 thou.saiid have long been known, was made up of a number of great 

 series, or complexes as LeConte called them, which, with some modifica- 

 tions of considerable importance, have been virtually accepted by ento- 

 mologists for a long time. Their relative positions, howeper, and their 

 equal or unequal taxonomic value have been a matter of considerable 

 difference of opinion ; there was a period of about a generation in length, 

 previous to 1850, in which questions of this kind received a very large 

 share of attention from leading entomologists, but the general consensus 

 of opinion seemed to chrystallize toward the view expressed by Lacor- 

 daire in his great work on the genera of Coleoptera commenced in 1854, 

 and this consensus was very closely reflected in the first edition of the 

 •'Classification of the Coleoptera of the North America,"— not in any 

 nomenclature of the complexes, for these were not even mentioned, but 

 in the order in which the families followed one another. This succession 

 was as follows: 1, Adephaga ; 2, Clavicornia ; 8, Lamellicornia ; 4, Ser- 

 ricornia ; 5, Heteromera. Beyond this, as stated earlier, the work did 

 not proceed, as here, according to the accepted classification, the Rhyn- 

 chophora were reached, but in 1873, the concluding part of the earlier 

 edition was published, treating a portion of the Phytophaga, making 



