680 STAPHYLINIDA. 
broadly explanate-elevate. The terminal ventral rings are almost without sculpture. 
Two decayed examples. 
7. Osorius opacifrons. 
Cylindricus, nigricans, minus nitidus ; antennis pedibusque rufis; sublevigatus, capite peropaco. 
Long. 8 millim. 
Hab. Mexico (Chasles, in coll. Chevrolat). 
This insect is extremely similar to 0. doops, but has the eyes less convex, and also 
exhibits some other distinctions. The front of the clypeus is broad, simply emarginate. 
The eyes are slightly convex. The surface of the head is remarkably dull, and punctures 
can scarcely be detected on it. The thorax is broad, a little sinuate at the sides behind, 
where the lateral margins are slightly, but distinctly, elevated, the angles rectangular ; 
it is very finely and sparingly punctate, and there is a very obsolete channel along the 
middle. The elytra are almost impunctate, and the terminal ventral segments without 
sculpture. Unique. 
§2. Lateral margins of the thorax not more elevated behind ; thorax not canaliculate, 
but with a median smooth space, which is usually limited on each side by serial 
punctures. 
8. Osorius cylindricus. 
Osorius cylindricus, Latr. Nouv. Ann. Mus. Hist. Nat. 1. p. 86 1; Er. Gen. et Spec. Staph. p. 756°. 
Hab. Mexico !, Orizaba (Deppe?), Jalapa (Flohr, Hoge), Cordova (Sallé). 
9. Osorius germanus. 
Sat latus, nigricans, nitidus; antennis pedibusque rufis; capite, prothorace elytrisque parce subtiliterque 
punctatis, hoc medio anguste longitudinaliter levigato. 
Long. 7 millim. 
Hab. Guavemata, near the city, Capetillo, Duefias (Champion). 
This insect is extremely close to O. cylindricus, but is broader than the broadest and 
largest examples of that species, and readily distinguished by the much finer punctua- 
tion of the thorax. From the following species it may be known by the fact that, 
though there is an indefinite smooth space along the middle of the thorax, this space 
is not bounded by any serial punctures. The punctuation of the ventral plates of the 
last two segments is less than in O. cylindricus. Sixteen examples. 
10. Osorius parcus. 
Cylindricus, nigricans, nitidus; antennis pedibusque rufis; capite dense subtiliterque coriaceo, opaco, parcius 
subtiliter punctato; prothorace parce punctato, medio area lata levigata. 
Long. 7 millim. 
Hab. Muxico, Cordova (Hége); Guaremata, Panzos, Cubilguitz, and San Juan in Vera 
