62 R. W. Dawson 



under surface of the head and the antennae; surface of body and 

 elytra either dull or polished 8 



8. Mandibles visible beyond the clypeus 12 



Mandibles not visible beyond the clypeus 9 



9. Hind tarsi vi^ith short, triangular segments, the basal ones con- 

 spicuously wider than the terminal (p. 190) Psammohiiis 



Hind tarsi v^^ith longer nearly cylindrical segments, the basal 

 ones but little wider than the terminal 10 



10. Surface of head and pronotum roughly granulate; pronotum 

 with three or four raised, transverse lines (p. 190) Rhyssemus 



Surface of head and pronotum punctured instead of granulate; 

 pronotum without transverse, raised lines 11 



11. Outer, dorsal angle of hind tibiae prolonged and spine-like 

 (p 187) Ataenius 



Outer, dorsal angle of hind tibae not prolonged into a spine 

 (p. 180) Aphodius 



12. Pronotum and elytra with fine, short, semi-erect, yellow hair..., 17 

 Pronotum and elytra v/ithout fine yellow hair 13 



13. Size small, 5 mm. or less in length (p. 180) Aegialia 



Size larger, 7-20 mm. in length 14 



14. Surface of pronotum evenly convex, not coarsely punctured 

 (p. 195) Geotrupes 



Surface of pronotum not evenly convex, more or less grooved, 

 ridged, or tuberculate, coarsely and unevenly punctured 15 



15. Eyes entirely divided into an upper and lower portion 16 



Eyes only partially divided (p. 195) Eucanthus 



16. Mesosternum strongly elevated between and in front of the 

 middle coxae which are narrowly separated by a metasternal 

 process extending forward and uniting with the mesosternal 

 prominence (p. 194) Bolbocerosoma 



Mesosternum not elevated between and in front of the middle 

 coxae; the coxae nearly or quite contiguous (p. 193) Odontaeiis 



168 



