604 STAPHYLINIDA. 
We have only a single very immature example of this species, but it is so certainly 
distinct that I do not hesitate to give it a name; the colour may be darker (possibly 
black, as in D. laticeps) in the mature state. D. robustus is much broader than any of 
the allied insects; the head is broad, with the hind angles rounded, in shape very 
much like that of Stilicus, and densely reticulate. Thorax a little longer than broad, a 
little narrowed behind and greatly so in front, reticulate like the head. Elytra broad, 
rather longer than the thorax, coarsely and closely punctured, the hind margin irregu- 
larly of a flavescent colour, as in D. posticalis. Hind body densely, rather finely 
punctate. 
6. Dibelonetes posticalis. 
Latiusculus, niger; antennis, palpis, pedibus elytrorumque apice flavis, femorum posteriorum apice anguste 
fuscescente. 
Long. 43 millim. 
Hab. Guatemata, Cerro Zunil, El Tumbador, Las Mercedes (Champion). 
Antenne only moderately long and slender, evidently thicker at the extremity ; 
penultimate joint scarcely longer than broad. Thorax a little narrowed behind, more 
abruptly so in front, the lateral angles a little more distinct than in D. laticeps (so that 
the shape is like that of the species of Sfilicus); rather coarsely rugose-punctate, 
the head being reticulate. Elytra broader and a little longer than the thorax, 
deeply and distinctly punctured; the hind margin rather broadly yellow, but the dark 
colour at the suture reaches the apex. Hind body densely and finely but distinctly 
punctate. Hind femora distinctly, the middle femora indistinctly, fuscescent at the 
extremity. Male with the hind margin of the terminal ventral segment broadly and 
deeply excised, that of the penultimate segment broadly but less deeply. 
Though closely allied to D. laticeps, this insect is distinguished from it by numerous 
details. Swnius hybridus, Er., appears, from the description, to be also very near to 
D. posticalis. 
7. Dibelonetes panamensis. 
Niger, antennis, palpis, pedibus elytrorumque apice flavis, femorum apicibus fuscis. 
Long. 47 millim. 
Hab. Panama, David (Champion). 
Antenne only moderately long, thicker externally; penultimate joint transverse, the 
basal joint quite as long as the three following together. Head only moderate in width, 
the vertex completely rounded, the surface strigose. Thorax slender, much narrowed 
behind, and still more so in front. Elytra as long as the thorax, coarsely, deeply and 
distinctly punctured ; hind margin of each with a rather large yellow spot. Hind body 
densely punctate. Hind and middle femora fuscescent externally. 
A single fragmentary example of the female is all that has been found. The species 
has shorter antenne and wing-cases than D. posticalis, and a narrower thorax. 
