92 



COLEOPTERA OP NORTH AMERICA. 



5. First three dorsal segments normal. 6. 

 First three dorsal segments with lateral tufts of hairs. Lomechusa. 



6. First joint of hind tarsi very long. 7. 

 First joint of hind tarsi less elongated; 3d joint of maxillary palpi 



strongly inflated. Callicerus. 



7. Middle coxse snhcontiguous ; antennie long and slender. Tachyusa. 

 Middle coxae distant ; antennae stouter. Myrnaedonia. 



Head prominent, narrowed at base. 2. 



Head retracted, not narrowed at base. 5. 



2. First joint of hind tarsi longer than 2-3 united. ' 3. 

 First joint of hind tarsi shorter than 2-3 united. Phlceopora. 



3. Mesosternum not carinate ; 4 

 Mesosterniim carinate ; ligula short. Ilyobates. 



4. Ligula short. Calodera. 

 Ligula long. Ocalea. 



5. Palpi normal ; maxillary 4-jointed, labial 3-jointed. G. 

 Palpi with accessory terminal joint ; Aleochara. 



6. Ligula entire. 7. 

 Ligula bifid. 8. 



7. Body very broad and flat ; maxillary palpi with 3d joint elongate. 



Homoeusa. 



Body narrow. Haploglossa. 



8. Mandibles entire at tip ; dorsal segments 1-3 transversely im- 



pressed. «'. 



Mandibles cleft at tip. Dasyglossa. 



9. Labial palpi with joints gradually narrower. 10. 

 Labial palpi with joints 1-2 thick ; maxillary palpi with 3d joint not 



inflated. Thiasophila. 



10. Maxillary lobe normal in form. *Oxypoda. 



Maxillary lobe with several processes at tip. Polylobus. 



Head strongly constricted behind into a narrow neck. 2 



Head not strongly constricted behind. 3. 



Labial palpi 3-jointed. Autalia 



Labial palpi 2-jointed. Eudera 



Front and middle tibiae pubescent. 4. 



Front and middle tibiae with spines on outer margin. Phytosus. 



Labial palpi 2-jointed. 5. 



Labial palpi 3-jointed, 7. 



* The genera Euthorax and Myrmecochara, which also enter into our 

 fauna, are not sufficiently distinct to find a place in the table ; and in fact 

 we have great doubt that tliey should be continued as distinct. 



