102 COLEOPTERA OF NORTH AMERICA. 



The genus Monotonia, introduced into this family by many 

 authors, does not belong to it, and will be found in the faniily 

 Monotoniidae. 



I have also excluded from the family Gorticaria irisignata 

 Mann., which, with Cryptopjhagus macirfatus Mels., must form a 

 new genus, Derodontus ; its systematic place is in a new family. 



Our genera are related as follows : — 



Antennae with a distinct 2-jointed club ; labial palpi 3-jointed. 



HoLOPARAMECUS. 



Antennae with the outer joints enlarged ; labial palpi 2-jointed; 

 Antennae gradually thickened, last joints confused;* thorax wide. 



Bonvouloikia. 

 Antennae 11-jointed ; club 3-jointed ; thorax narrower than the elytra ; 

 Thorax strongly margined ; second joint of tarsi not shorter than the 



first. Lathridics. 



Thorax not margined ; second joint of tarsi shorter than the first. 



Cokticaria. 



To Bonvouloiria belongs the Californian Laihridius parviceps 

 Lec.f A species of Holoparamecus was found by me at Fort 

 Yuma, California. The other two genera are represented on 

 both sides of the continent. 



Fam. XXIV.— OTHNIIDAE. 



Mentum trapezoidal, truncate in front; ligula corneous; 

 palpi cylindrical, 8 -jointed, third joint longer than the others. 



Maxillae exposed at the base (lobes not seen); palpi 4- 

 jointed, cylindrical, last joint longer than the others. 



Antennae inserted under the sides of the front, before the 

 eyes, 11-jointed, first joint thicker than the following, third 

 longer than the first and second together, 9 — 11 broader, 

 forming a loosely articulated club. 



Head large and flat, sides of the front oblique in front of 

 the eyes ; labrum very short, closely articulated with the 

 front, ciliate anteriorly ; mandibles short, emarginate at tip ; 

 eyes large, prominent, finely granulated. 



Prothorax quadrate, not wider than the head, feebly 

 serrate on the sides, with the angles rounded; side pieces 



* Duval describes the antennae of the European species as 9-jointed ; 

 those of the American species appear to have ten joints, 

 t Proc. Acad. Nat. Sci., vii. 304. 



