78 SILPHIDZ. 
middle. Mundibles diverse in shape, one being sharply hooked, and armed with a sharp tooth below the 
hooked apex, the other shorter and almost simple. Mawille short and stout, bilobed, with the outer 
lobe short and broad, furnished with very long incurved sete at the extremity ; inner lobe large and 
broad, ciliated on the inner edge; stipes short and robust. Mentwm short and very broad, hollowed in 
the middle, and much rounded at the anterior angles. Labiwm rather small, suboblong, and produced 
anteriorly between the palpi. Lingua small, apparently subquadrate. Prosternwm small ; episterna small, 
triangular ; epimera rather large, partly enclosing the coxal cavities; coxal cavities large, contingent, 
open both in front and behind, with a large foramen at the outer extremity. Mesosternwm moderate, not 
much excised in front; episterna moderate, rather narrow; epimera long and oblique, reaching to the 
coxal cavities ; coxal cavities exceedingly large, suboval, with a large foramen at the outer extremities, 
nearly contingent. Metasternum large, transversely oblong, nearly reaching to the sides of the body, and 
produced posteriorly into two short, but very acute denticulations between the coxe; episterna long and 
very narrow, not so long as the metasternum ; epimera very long, extending beyond the coxe. Venter 
composed of five segments; the basal segment twice as long as either of the others and slightly 
but broadly elevated in a curved line at its base, enclosing the whole length of the coxa; the other 
segments nearly equal to each other in length. Legs very slender: anterior rather short, with the femora 
laminated on the inside ; tibiee not dilated, armed with short apical spurs; tarsi 3-jointed in the female, 
indistinctly 4-jointed in the male; claws very slender, simple; intermediate rather longer, with the 
femora robust, broadly laminated on the inside ; tibiee setose, armed with apical spurs ; tarsi 3-jointed in 
both sexes, the basal joint long, and furnished with short setse on the sides; posterior similar to the inter- 
mediate, but longer. Cove: anterior large, subconical, contingent and very prominent; intermediate very 
large, not contingent, prominent; posterior large, nearly reaching the sides of the body, separated by the 
bitid process of the metasternum. 
Aglyptus, first characterized as a genus by Dr. Leconte, from a species of rare 
occurrence in the United States, appears to be the prevailing form of the “ Anisoto- 
mina” in Central America, where at least two species seem to be abundant. In the 
whole of the external skeleton the genus much resembles Scotocryptus and Creagro- 
phorus: all are alike in the shape of the prosternum, with its doubly open coxal cavities, 
and in this respect also resemble Agathidium ; but they differ from that genus in many 
particulars, and especially in the elevated portion of the first ventral segment, and in 
the transverse strigation of the posterior femora, these characters separating them from 
other genera of this tribe. From Scotocryptus and Creagrophorus, Aglyptus may be 
known by its long and diversely formed antenne and slender legs. 
1. Aglyptus horni, sp.n. (Tab. III. fig, 3.) 
Late ovalis, validissime convexus, castaneus, glaber, nitidissimus, punctis minutis totus indistincte notatus ; 
capite modico, epistomate semiovali, flavo, ore flavo, prominente; oculis magnis, valde prominentibus ; 
pronoto quam caput latiore, vix longiore, ad basin latissimo, margine anteriore atque lateribus flavescentibus, 
marginatis et reflexis, angulis anterioribus parum productis, margine basali fere recta angulis fere rectis ; 
elytris semiovalibus, quam caput atque pronotum longioribus, vix latioribus, ad humeros latissimis, stria 
suturali indistincta impressis, lateribus rotundatis, late marginatis, apice obtuso; pedibus modicis, 
gracilibus, rufo-testaceis, tarsis triarticulatis; antennis longis, gracilibus, rufo-testaceis, articulis quinque 
apicalibus obscuris. Long. corp. 1;%, lin.=2°25 millim. 
Body broadly oval, exceedingly convex, castaneous, smooth and very shining, marked throughout with minute 
and very indistinct punctures. Head moderate; epistoma semioval, yellow ; mouth prominent, yellow ; 
eyes large and very prominent; antenne long and slender, rufo-testaceous, with the apical five joints 
dusky. Thorax broader, but scarcely longer, than the head, widest at the base; anterior margin and 
sides flavescent, margined and reflexed; anterior angles slightly produced; basal margin nearly straight, 
