Coleopterological Notices, V. 443 



Antennae sliglitly less approximate, the frontal tubercle shorter and wider but 

 very pronounced, with the sides behind it constricted, the antennal 

 prominences narrowly separated by a very deep sulcus ; antennae as in 

 Oropus ; ungual appendage visible but exceedingly minute Morius 



Antennae not inserted on a frontal tubercle, more or less widely distant at 

 base 2 



2 — Antennae geniculate, the basal joint elongate ; prothorax bilobed ; appen- 

 dage of the tarsal claw distinct RliexiUS 



Antennae not geniculate, the basal joint normal 3 



3 — Ungual appendage long and conspicuous, approaching one-half the length 

 of the principal claw 4 



Ungual appendage more or less minute, but generally visible, in some cases 

 apparently obsolete 5 



4 — Prothorax with an acute marginal tooth at each side near the base ; first 

 dorsal segment longer than the second ; male sexual modifications afi"ect- 

 ing the fourth dorsal segment OropilS 



Prothorax without lateral spines, but frequently minutely and unevenly 

 crenulate along the sides in basal half; first dorsal not distinctly longer 

 than the second. 

 Head more transverse ; body shorter ; pronotum with a fine subentire median 

 groove ; secondary male sexual characters affecting the fourth tergite. 



Rhexidiiis 

 Head less transverse ; body longer, more parallel ; pronotum without discal 

 impression ; male characters near the apex of the abdomen beneath, or 

 near the middle of the lateral edges ; maxillary palpi partially received 

 in deep sublateral fossae, which are separated from the cardo of the max- 

 illae by minute slender porrect processes Railiecia. 



5 — Antennal club gradually formed, the last joint relatively moderate in 

 size 6 



Antennal club consisting almost entirely of the larger abrupt terminal joint ; 

 pronotum without discal impressions ; first dorsal segment subequal to 

 the second 12 



6 — Presternum not carinate along the middle 7 



Prosternum finely but strongly carinate in the middle throughout the length ; 

 antennae less distant than in Euplectus 11 



^ — Prosternum with two distant diverging longitudinal carinae ; elytra with 

 two discal striae and three basal foveae ; abdomen without trace of basal 

 impressions or carinae, the segments equal in length Oropodes 



Prosternum without diverging lines ; abdomen at least impressed at the middle 

 of the first two or three dorsal segments 8 



8 — First dorsal not longer than the second ; palpal fossae wide, shallow, more 

 inferior and posterior, and not separated from the maxillae by porrect 

 processes 9 



First dorsal much longer than the second 10 



9 — Eyes large, bordered above and beneath by a broad abrupt channel ; pro- 

 notum with three very large, feebly connected, subbasal excavations, 

 without discal impression ; elytra and sexual characters as in Euplectus. 



Acolonia 



