^Nyb* Le Conte's Monography of 



wiiile the young of the true plagyrus bear a close resemblance 

 to the old. This last species is found in every spring, run and 

 rivulet in Ohio, and the former I have never met vi^ith except 

 in the waters of the lake, where it is frequently taken in seines 

 while fishing for other species. It aflbrds me pleasure to ded- 

 icate it to my friend D. Humphreys Storer, M. D., to whom I 

 am indebted for essential aid, and many important suggestions, 

 in arranging and describing our western fishes. 



Art. III. —a monography OF THE NORTH AMERICAN HISTE- 

 ROIDES. By John Le Conte, F. L. S., &c. Communicated Sept. 10, 1844. 



The little attention which has been paid to Entomology in 

 this country, has left the greater portion of our insects entirely 

 unknown ; and we are chiefly indebted to foreigners, for the 

 names and descriptions of those with which we are acquainted. 

 The difficulty of ascertaining even these is justly much com- 

 plained of; for nowhere can be found collected together the 

 various works through which they are scattered. In order, as 

 far as possible to remedy this inconvenience, I have proposed, 

 in conjunction with my son, to draw up from time to time mon- 

 ographies of such genera of Coleoptera as may appear most 

 worthy of investigation. Those which contain the greatest 

 number of new species, may not always prove the most so ; 

 therefore, in selecting the family of the Histeroides for the first 

 of the series, although the greater part of the species have 

 been long known, it is hoped that it will not prove one of the 

 least interesting. 



In the year 1811, when Baron PaykuU pubhshed his Mon- 

 OGRAPHiA HisTERoiDUM, hc was able to describe but ninety- 

 three species, of which, he considered about fourteen as 

 natives of North America. Twenty-six years after this, 

 Count Dejean, in his catalogue of the insects in his collection, 

 enumerated two hundred and fifteen, of which, thirty-three had 



