June 20, 1S73.] — * ^ [Horn. 



SYNOPSIS OF THE HISTERID.E OF THE UNITED STATES. 

 By George H. Hokn, M.D. 



{Read before the American PliilosopMcal Society, June 30, 18To.) 



It is now twenty-eight years since tlie revision of the species of this 

 family by Major John Leconte, and it lias appeared to me that the time 

 \\i\s, arrived when a second revision is much needed. All the species 

 known to Marseul have been described by him in his very exhaustive 

 Monograph, and in supplements published from time to time, any new 

 or old species previously unknown to him have been fully described. 

 Numerous species are, however, still unknown in nature to Marseul, and 

 his work is to that extent incomplete. To the lai"ge majority of our 

 students, Marseul' s Monograph is practically inaccessible, and as it deals 

 with the species of the entire globe, the student of a limited fauna like 

 our own finds it no easy matter to deal with the subject rendered all the 

 more difficult by the vast number of species. 



In the preparation of this essay I have availed myself of the cabinet 

 and library of Dr. Leconte, which have at all times been as accessible as 

 if ihey were my own. At this time I must also I'ccord the great kindness 

 of M. de Marseul, who. through the kind intercession of M. Aug. Salle, 

 loaned me many of his unique types for study, and also a similar favor 

 on the part of M. Chevrolat. By these kind acts I have had before me 

 for personal inspection, either the types of the majority of our species or 

 those which are almost types by comparison with the types of authors. 



The subdivision of the genera of this family into two tribes appears to 

 me the most natural method, viz. : 



Head porrected, mandibles very prominent HOLOLEPTINI. 



Head retracted, bend downward, mandibles not very 



prominent HISTRINI. y 



Tribe HOLOLEPTINI. 



This tribe contains in our fauna but one genus, Ilololepta, formed bj"^ 

 the union of that genus as recognized by 3Iarseul and Lionota, the difter- 

 ences between the two do not appear to be sufficient for their separation. 



HoLOLEPTA. Payk. 



Head prominent, mandibles long produced in the plane of the body, 

 not toothed, inner edge grooved in nearly their entire length for the 

 reception of the maxillae. Labrum deeply and broadly grooved apex, 

 strongly bent downwards and triangular; on each side slightly notched 

 by the mandibles. Mentum large, entirely corneous, triangularly emar- 

 ginate in front for the reception of the tip of the labrum. Anterior 

 tibia? dentate on the inner edge at base, very near the articulation. 



By means of these characters the genus Ilololepta may be known from 

 all those which follow. The antenna} are inserted under the margin of 

 A. p. s. — VOL. XIII. 2r 



