126 cOleoptera of north America. 



will enable them to be readily distinguished from any of the 

 neighboring families. 



The introduction of Murraidius from the Histerid* seems to 

 indicate the division of the family into two sub-families. 



Antennae inserted nnder a distinct frontal ridge, anterior coxse distant 

 from the mesosternum. Colydiin^. 



Antennffi inserted on tlie front, anterior cox;e inclosed behind by the 

 inesosternum. MuEMiDiiN/ii:. 



Sub-Family I._COLYDIIN^. 



The genera of this sub-family are numerous, and are divisible 

 into tribes in the following manner: — 



Antennse capitate, retractile, arising close to the eyes. 2. 

 Antenna3 perfoliate, not retractile, distant from the eyes. Rhagodcrini. 



2. Last joint of palpi not acicular. 3. 

 Last joint of palpi acicular. 6. 



3. Front coxse slightly separated ; head horizontal. 4. 

 Front coxse distant. 5. 

 Front coxse nearly contiguous; head defiexed. Deretaphrini. 



4. First joint of tarsi short. Synchitini. 

 First joint of tarsi longer than the second. Colydiini. 



f). Antennse arising under a frontal margin ; first ventral segment not 

 elongate ; trochanters free. Pycnomerini. 



Antennse free at base; first ventral elongate; trochanters closely con- 

 nate with the femora. Bothriderini. 



6. First ventral elongate ; antennse free at base. Cerylonini. 



Tribe L—RHAGODERIXI. 



Elongate, eostate, bristly species, represented by two genera 

 which occur in the Pacific region, and indicate separate sub- 

 tribes. 

 Anterior coxal cavities open behind ; eyes entir.-. Sub-tribe Ritagoderini. 



Head narrowed behind, forming a distinct neck. Rhagodera. 



Anterior coxal cavities closed behind ; eyes divided. Hub-tribe Anchommini. 



Head not narrowed behind. Anchomma. 



Tribe 11.— SYNCHITIi\l. 



The genera are numerous, elongate or oval in form, and usually 

 eostate and bristly. 



